How does a Sync port work?

Started Sep 26, 2016 | Discussions
PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea
2

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

dlevitt Contributing Member • Posts: 707
Re: Maybe not the best idea

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

There is a high speed solid state switch called a Thyristor [ https://en.wikipedia.org/wiki/Thyristor ]. [An obsolete version used a similar switch to divert the flash pulse from the flash tube to an internal 'quench tube'. This had the disadvantage of always being a full discharge on the flash's capacitors]

Flashes have some common power settings - the full, half, quarter power settings are switched relative the flash's full power output.

The various auto modes have an 'enough light' signal sent from a photocell on the flash, or from sensors inside the camera [through the lens] flash metering.

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

-- hide signature --

Save the Earth! Collect the entire set!

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PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Well it helps that the "speed of light" is 186,000 miles/sec.

So it is not impossible to generate light, (which travels to -- AND FROM -- the subject @ 186,000 miles/sec), and then READ THE REFLECTED LIGHT BACK FROM THE SUBJECT.

And since the speed of "electrons" is also 186,000 mi/sec, it is possible to "stop" the generated light when it is determined the necessary amount has reached the subject.

The original "auto" strobes used a sensor combined with the flash unit, but their "reading" angle was fixed and did not necessarily match the lens.

With TTL, (Through The Lens metering), the sensor is within the camera itself and thus could match the lens and metering preset within the camera.  With TTL, the camera itself replaces the (former auto) sensor on the flash and thus more accurate to the selected lens mounted on the camera.

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

And more recently it can be done via THYRISTORs.

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Leonard Migliore
Leonard Migliore Forum Pro • Posts: 18,332
Re: Maybe not the best idea
2

PhotoTeach2 wrote:

Now that I have told the "secrets", I have to KILL everyone !!!

No, you just have to kill everyone that can read. That's a much easier job.

-- hide signature --

Leonard Migliore

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PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

Leonard Migliore wrote:

PhotoTeach2 wrote:

Now that I have told the "secrets", I have to KILL everyone !!!

No, you just have to kill everyone that can read. That's a much easier job.

Well, if only those that can "read" ... good thing that does not include "me" !!!

OP OmarAl New Member • Posts: 21
Re: Maybe not the best idea

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Very interesting, but I suppose that as long High Sync Speed is available then this shouldn't be much of a problem, it too has been around for a long time too.

If I am correct, the technique of High Sync Speed is basically a Strobe or Flash firing multiple bursts of light in order to expose the sensor properly right??

Sigh...you don't understand how long I have been waiting for a modern digital SLR to carry a Global Shutter sensor, I am absolutely sick and tired of the Rolling Shutter effect! I do a lot of videowork by the way

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

So let me get this straight, Flashtubes are a type of Xenon lamps that can't last for no more than a second whereas a Xenon headlight is another type that can work as continuous light??

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

Vivitar must've have certainly made a lot of money based on this fact alone. It's a shame its current products are produced in China and its originators have passed away

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

Now this is becoming more clear, although I really don't understand it much

Is it quite easy to create and implement? Theoretically, could it be used in my LED Ring Flash perhaps??

Another thing I am trying to understand with this as well is the timings...does it shut off as soon as the shutter contact is made? or a tiiiinyyy bit after the contact??

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Very interesting, but I suppose that as long High Sync Speed is available then this shouldn't be much of a problem, it too has been around for a long time too.

If I am correct, the technique of High Sync Speed is basically a Strobe or Flash firing multiple bursts of light in order to expose the sensor properly right??

YES ... It basically "extends" the flash duration to 1/200sec+ by pulsing the strobe.

BUT ... While there are some usefulness to HSS .... there are MAJOR PROBLEMS with it also.

The effective power of the strobe is reduced, (as much as 1/10 normal full-power), thus it has VERY LIMITED range in HSS mode.

Indeed the main advantage of a native (high) flash-sync speed, (like 1/1000 & 1/4000sec on FZ-1000) Is a much longer effective fill-flash range in daylight. (and also "darken" the backgrounds on closer subjects)

Sigh...you don't understand how long I have been waiting for a modern digital SLR to carry a Global Shutter sensor, I am absolutely sick and tired of the Rolling Shutter effect! I do a lot of videowork by the way

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

So let me get this straight, Flashtubes are a type of Xenon lamps that can't last for no more than a second whereas a Xenon headlight is another type that can work as continuous light??

Well ... I think that is a "yes". The secret to them both is that they generate light from an "arc".

If you know anything about the old WW2 "searchlights" which were used to illuminate enemy bombers up to 20,000' high.

These were then sold as war-surplus and used to attract people to "grand-openings" and other events. Note that they could be seen for many-many-many miles away and people would rush to them to see what was "happening".

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

Vivitar must've have certainly made a lot of money based on this fact alone. It's a shame its current products are produced in China and its originators have passed away

Yep, it was the most popular strobe for many years.

But I repeat again, DON'T use one on digital if you find an "old" one because they had 250vdc on the contacts and will blow the digital cameras w/ SCR/TRIACS.

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

Now this is becoming more clear, although I really don't understand it much

Is it quite easy to create and implement? Theoretically, could it be used in my LED Ring Flash perhaps??

Absolutely NOT ... it is not at all the same/similar technology.

Another thing I am trying to understand with this as well is the timings...does it shut off as soon as the shutter contact is made? or a tiiiinyyy bit after the contact??

It "starts" with the first contact, which fires the main SCR/TRIAC, to start the discharge of the main capacitor.

Then there is a light sensor on either the flash itself, or in the camera if TTL, and that determines when sufficient light has hit the subject, (and bounced back to the sensor/TTL).

WHEN sufficient light has hit the subject, it fires the "cut-off" SCR/TRIAC and the flash is immediately stopped/extinguished by stopping the discharge of the main capacitor.

Note that first/earlier auto strobes used to stop the arc by "shorting" the remaining charge of the capacitor away from the flash-tube. BUT ... that meant that the capacitor had to "fully" recharge every time, (because it had been "discharged" by the "shorting" circuit). That meant a "time" was required before the flash could be used again because it had to "fully" recharge each time, (because it had been "fully" discharged).

With the later "forced-commutation" design, the capacitor retained the remaining charge and thus could often be immediately fired again with the remaining charge, (or would recharge faster).

BTW: I have not worked in electronics for several years.  It is possible that there are newer "switching" devices that do not require the "forced commutation" design.

BUT ... the THEORY is still the same.  The flash is started by the "contacts" in the camera, and then an auto sense device, (now usually TTL in camera), determines the sufficient amount of light, and then (immediately) STOPS the light output, (in as short as 1/50,000sec if "close" range subject).

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

OP OmarAl New Member • Posts: 21
Re: Maybe not the best idea

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Very interesting, but I suppose that as long High Sync Speed is available then this shouldn't be much of a problem, it too has been around for a long time too.

If I am correct, the technique of High Sync Speed is basically a Strobe or Flash firing multiple bursts of light in order to expose the sensor properly right??

YES ... It basically "extends" the flash duration to 1/200sec+ by pulsing the strobe.

BUT ... While there are some usefulness to HSS .... there are MAJOR PROBLEMS with it also.

The effective power of the strobe is reduced, (as much as 1/10 normal full-power), thus it has VERY LIMITED range in HSS mode.

Indeed the main advantage of a native (high) flash-sync speed, (like 1/1000 & 1/4000sec on FZ-1000) Is a much longer effective fill-flash range in daylight. (and also "darken" the backgrounds on closer subjects)

Ahhh okay, well 1/200th of a second is still pretty fast for my eyes, just probably not fast enough for some Inception or Bullet time effects

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

Sigh...you don't understand how long I have been waiting for a modern digital SLR to carry a Global Shutter sensor, I am absolutely sick and tired of the Rolling Shutter effect! I do a lot of videowork by the way

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

So let me get this straight, Flashtubes are a type of Xenon lamps that can't last for no more than a second whereas a Xenon headlight is another type that can work as continuous light??

Well ... I think that is a "yes". The secret to them both is that they generate light from an "arc".

If you know anything about the old WW2 "searchlights" which were used to illuminate enemy bombers up to 20,000' high.

These were then sold as war-surplus and used to attract people to "grand-openings" and other events. Note that they could be seen for many-many-many miles away and people would rush to them to see what was "happening".

Very very interesting piece of history there! Kind off answers a minor question of mine from years ago when I was younger

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

Vivitar must've have certainly made a lot of money based on this fact alone. It's a shame its current products are produced in China and its originators have passed away

Yep, it was the most popular strobe for many years.

But I repeat again, DON'T use one on digital if you find an "old" one because they had 250vdc on the contacts and will blow the digital cameras w/ SCR/TRIACS.

Okay okay I promise...I won't use one on a digital camera (however the chances of ever getting one is extremely slim)!

I'm sorry

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

Now this is becoming more clear, although I really don't understand it much

Is it quite easy to create and implement? Theoretically, could it be used in my LED Ring Flash perhaps??

Absolutely NOT ... it is not at all the same/similar technology.

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

Another thing I am trying to understand with this as well is the timings...does it shut off as soon as the shutter contact is made? or a tiiiinyyy bit after the contact??

It "starts" with the first contact, which fires the main SCR/TRIAC, to start the discharge of the main capacitor.

Then there is a light sensor on either the flash itself, or in the camera if TTL, and that determines when sufficient light has hit the subject, (and bounced back to the sensor/TTL).

WHEN sufficient light has hit the subject, it fires the "cut-off" SCR/TRIAC and the flash is immediately stopped/extinguished by stopping the discharge of the main capacitor.

Note that first/earlier auto strobes used to stop the arc by "shorting" the remaining charge of the capacitor away from the flash-tube. BUT ... that meant that the capacitor had to "fully" recharge every time, (because it had been "discharged" by the "shorting" circuit). That meant a "time" was required before the flash could be used again because it had to "fully" recharge each time, (because it had been "fully" discharged).

With the later "forced-commutation" design, the capacitor retained the remaining charge and thus could often be immediately fired again with the remaining charge, (or would recharge faster).

BTW: I have not worked in electronics for several years. It is possible that there are newer "switching" devices that do not require the "forced commutation" design.

BUT ... the THEORY is still the same. The flash is started by the "contacts" in the camera, and then an auto sense device, (now usually TTL in camera), determines the sufficient amount of light, and then (immediately) STOPS the light output, (in as short as 1/50,000sec if "close" range subject).

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Very interesting, but I suppose that as long High Sync Speed is available then this shouldn't be much of a problem, it too has been around for a long time too.

If I am correct, the technique of High Sync Speed is basically a Strobe or Flash firing multiple bursts of light in order to expose the sensor properly right??

YES ... It basically "extends" the flash duration to 1/200sec+ by pulsing the strobe.

BUT ... While there are some usefulness to HSS .... there are MAJOR PROBLEMS with it also.

The effective power of the strobe is reduced, (as much as 1/10 normal full-power), thus it has VERY LIMITED range in HSS mode.

Indeed the main advantage of a native (high) flash-sync speed, (like 1/1000 & 1/4000sec on FZ-1000) Is a much longer effective fill-flash range in daylight. (and also "darken" the backgrounds on closer subjects)

Ahhh okay, well 1/200th of a second is still pretty fast for my eyes, just probably not fast enough for some Inception or Bullet time effects

1/200sec is horribly LONG, (for many purposes). Especially if using telephoto lenses.

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

Sigh...you don't understand how long I have been waiting for a modern digital SLR to carry a Global Shutter sensor, I am absolutely sick and tired of the Rolling Shutter effect! I do a lot of videowork by the way

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

So let me get this straight, Flashtubes are a type of Xenon lamps that can't last for no more than a second whereas a Xenon headlight is another type that can work as continuous light??

Well ... I think that is a "yes". The secret to them both is that they generate light from an "arc".

If you know anything about the old WW2 "searchlights" which were used to illuminate enemy bombers up to 20,000' high.

These were then sold as war-surplus and used to attract people to "grand-openings" and other events. Note that they could be seen for many-many-many miles away and people would rush to them to see what was "happening".

Very very interesting piece of history there! Kind off answers a minor question of mine from years ago when I was younger

They used carbon-rods and a very high voltage (and CURRENT) to generate a "arc" so was also very bright, (enough to reach 20,000'+).

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

Vivitar must've have certainly made a lot of money based on this fact alone. It's a shame its current products are produced in China and its originators have passed away

Yep, it was the most popular strobe for many years.

But I repeat again, DON'T use one on digital if you find an "old" one because they had 250vdc on the contacts and will blow the digital cameras w/ SCR/TRIACS.

Okay okay I promise...I won't use one on a digital camera (however the chances of ever getting one is extremely slim)!

Actually they are very common in pawn shops or ebay because there were so very MANY of them produced, (for many years).

I'm sorry

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

Now this is becoming more clear, although I really don't understand it much

Is it quite easy to create and implement? Theoretically, could it be used in my LED Ring Flash perhaps??

Absolutely NOT ... it is not at all the same/similar technology.

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Another thing I am trying to understand with this as well is the timings...does it shut off as soon as the shutter contact is made? or a tiiiinyyy bit after the contact??

It "starts" with the first contact, which fires the main SCR/TRIAC, to start the discharge of the main capacitor.

Then there is a light sensor on either the flash itself, or in the camera if TTL, and that determines when sufficient light has hit the subject, (and bounced back to the sensor/TTL).

WHEN sufficient light has hit the subject, it fires the "cut-off" SCR/TRIAC and the flash is immediately stopped/extinguished by stopping the discharge of the main capacitor.

Note that first/earlier auto strobes used to stop the arc by "shorting" the remaining charge of the capacitor away from the flash-tube. BUT ... that meant that the capacitor had to "fully" recharge every time, (because it had been "discharged" by the "shorting" circuit). That meant a "time" was required before the flash could be used again because it had to "fully" recharge each time, (because it had been "fully" discharged).

With the later "forced-commutation" design, the capacitor retained the remaining charge and thus could often be immediately fired again with the remaining charge, (or would recharge faster).

BTW: I have not worked in electronics for several years. It is possible that there are newer "switching" devices that do not require the "forced commutation" design.

BUT ... the THEORY is still the same. The flash is started by the "contacts" in the camera, and then an auto sense device, (now usually TTL in camera), determines the sufficient amount of light, and then (immediately) STOPS the light output, (in as short as 1/50,000sec if "close" range subject).

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

OP OmarAl New Member • Posts: 21
Re: Maybe not the best idea

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Very interesting, but I suppose that as long High Sync Speed is available then this shouldn't be much of a problem, it too has been around for a long time too.

If I am correct, the technique of High Sync Speed is basically a Strobe or Flash firing multiple bursts of light in order to expose the sensor properly right??

YES ... It basically "extends" the flash duration to 1/200sec+ by pulsing the strobe.

BUT ... While there are some usefulness to HSS .... there are MAJOR PROBLEMS with it also.

The effective power of the strobe is reduced, (as much as 1/10 normal full-power), thus it has VERY LIMITED range in HSS mode.

Indeed the main advantage of a native (high) flash-sync speed, (like 1/1000 & 1/4000sec on FZ-1000) Is a much longer effective fill-flash range in daylight. (and also "darken" the backgrounds on closer subjects)

Ahhh okay, well 1/200th of a second is still pretty fast for my eyes, just probably not fast enough for some Inception or Bullet time effects

1/200sec is horribly LONG, (for many purposes). Especially if using telephoto lenses.

Woops!

But I'm pretty certain that's usually the highest any speedlite would go.

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

This is precisely what I meant! Might as well shoot with continous light right?

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

In its time yes, but I mainly use it for video work and it still does a pretty good job, but I yearn so badly for a GH4, I just can never ever afford it

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time, how does it work? How does it know how to trigger X-amount of flashes in such a short space of time?

Is it an easy circuit to implement? Or does it get real complicated with this??

Sigh...you don't understand how long I have been waiting for a modern digital SLR to carry a Global Shutter sensor, I am absolutely sick and tired of the Rolling Shutter effect! I do a lot of videowork by the way

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

So let me get this straight, Flashtubes are a type of Xenon lamps that can't last for no more than a second whereas a Xenon headlight is another type that can work as continuous light??

Well ... I think that is a "yes". The secret to them both is that they generate light from an "arc".

If you know anything about the old WW2 "searchlights" which were used to illuminate enemy bombers up to 20,000' high.

These were then sold as war-surplus and used to attract people to "grand-openings" and other events. Note that they could be seen for many-many-many miles away and people would rush to them to see what was "happening".

Very very interesting piece of history there! Kind off answers a minor question of mine from years ago when I was younger

They used carbon-rods and a very high voltage (and CURRENT) to generate a "arc" so was also very bright, (enough to reach 20,000'+).

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

Vivitar must've have certainly made a lot of money based on this fact alone. It's a shame its current products are produced in China and its originators have passed away

Yep, it was the most popular strobe for many years.

But I repeat again, DON'T use one on digital if you find an "old" one because they had 250vdc on the contacts and will blow the digital cameras w/ SCR/TRIACS.

Okay okay I promise...I won't use one on a digital camera (however the chances of ever getting one is extremely slim)!

Actually they are very common in pawn shops or ebay because there were so very MANY of them produced, (for many years).

Looks like I'm going to have to avoid them like the plague!

I'm sorry

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

Now this is becoming more clear, although I really don't understand it much

Is it quite easy to create and implement? Theoretically, could it be used in my LED Ring Flash perhaps??

Absolutely NOT ... it is not at all the same/similar technology.

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Waaahhh...but how does it know when to stop the flash?

Another thing I am trying to understand with this as well is the timings...does it shut off as soon as the shutter contact is made? or a tiiiinyyy bit after the contact??

It "starts" with the first contact, which fires the main SCR/TRIAC, to start the discharge of the main capacitor.

Then there is a light sensor on either the flash itself, or in the camera if TTL, and that determines when sufficient light has hit the subject, (and bounced back to the sensor/TTL).

WHEN sufficient light has hit the subject, it fires the "cut-off" SCR/TRIAC and the flash is immediately stopped/extinguished by stopping the discharge of the main capacitor.

Note that first/earlier auto strobes used to stop the arc by "shorting" the remaining charge of the capacitor away from the flash-tube. BUT ... that meant that the capacitor had to "fully" recharge every time, (because it had been "discharged" by the "shorting" circuit). That meant a "time" was required before the flash could be used again because it had to "fully" recharge each time, (because it had been "fully" discharged).

With the later "forced-commutation" design, the capacitor retained the remaining charge and thus could often be immediately fired again with the remaining charge, (or would recharge faster).

BTW: I have not worked in electronics for several years. It is possible that there are newer "switching" devices that do not require the "forced commutation" design.

BUT ... the THEORY is still the same. The flash is started by the "contacts" in the camera, and then an auto sense device, (now usually TTL in camera), determines the sufficient amount of light, and then (immediately) STOPS the light output, (in as short as 1/50,000sec if "close" range subject).

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

Ahhh, this is where it gets interesting again! So you saying this is done by Positive Pulses you get in a waveform? This was something that was discussed previous in this topic. Or am I wrong?

How does it know when to stop at 1/1000th of a second?

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

I had to wonder about life the past three days, got lost a long the way, this is the reason why it took me until now to make a reply

PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

OmarAl wrote:

PhotoTeach2 wrote:

Very interesting you said that. So basically like a Xenon flashtube and a lightbulb, you're still discharging with the LED?

Well ... I think that is a yes ...

Very good, I should've known this already, I think it was because I'm typing all this in the early hours of the morning

But as you discovered and mentioned below, there is no "capacitor", (or at least not one in the same sense as there is in a flash/strobe where it is "the" essential component and the basics of its technology).

Yeah, you are correct. A flash or Strobe cannot live without it

Because of it's simplicity, does that mean it doesn't necessarily require a capacitor quick-fire rounds of flashes?

I would have to see the actual schematic to be more specific to a specific unit.

The other day I opened up my LED Ring Flash and from what I can see there is absolutely no capacitor, it's extremely simple, just a circuit board with a small chip inside. I also photographed it so I would've have to open it up again. Does it interest you to have a look at them perhaps??

Sure, but would be able to tell more from a schematic, (I am an electronic engineer so could immediately "read" it).

And yes, there is no "capacitor" in the sense there in in flash/strobe.

It is basically like a normal FLASHLIGHT / TORCH, (and the "chip" is probably a "timer").

I'll get the photos ready asap, but very interesting you mention about "timer", I thought the chip was there to control the buttons/functions of the flash device. It's funny as well, because everytime I trigger for the flash to go off I notice it's a bit slow, and that the flash duration last slightly longer than a normal flash does i.e. might not be very good for freezing fast action movements.

I could be wrong with all of this but might there be an explanation for this perhaps??

It's ability to "freeze" action/movement is of course the hallmark of strobes.

Yes! And this is the exact reason I was trying to explain in my previous post(s)! Something like a Speedlite will just simply not work in some/many scenarios!

Well, it won't work if you want "continuous" light, (like for VIDEO).

BUT ... for most "photographic" purposes the shorter (action-stopping fast) flash is much, much better.

It can be MUCH brighter and "action-stopping" is almost always an advantage.

HOWEVER ... because it is so short, HSS techniques must be used to deal with the 1/200-1/250 shutter "duration" of a focal-plane shutter.

BUT ... That can't be described as a "disadvantage" of the (short/fast duration of) strobes, but rather a (VERY BIG) disadvantage of focal-plane shutters.

MirrorLess cameras are a very big jump forward in new-technology, BUT ... many still have to use focal-plane shutters so the next step forward is "global-shutters".

My FZ-1000 uses "leaf" shutters, and thus has a 1/4000 flash-sync speed, but supposedly "global" shutters are supposed to be better.

Very interesting, but I suppose that as long High Sync Speed is available then this shouldn't be much of a problem, it too has been around for a long time too.

If I am correct, the technique of High Sync Speed is basically a Strobe or Flash firing multiple bursts of light in order to expose the sensor properly right??

YES ... It basically "extends" the flash duration to 1/200sec+ by pulsing the strobe.

BUT ... While there are some usefulness to HSS .... there are MAJOR PROBLEMS with it also.

The effective power of the strobe is reduced, (as much as 1/10 normal full-power), thus it has VERY LIMITED range in HSS mode.

Indeed the main advantage of a native (high) flash-sync speed, (like 1/1000 & 1/4000sec on FZ-1000) Is a much longer effective fill-flash range in daylight. (and also "darken" the backgrounds on closer subjects)

Ahhh okay, well 1/200th of a second is still pretty fast for my eyes, just probably not fast enough for some Inception or Bullet time effects

1/200sec is horribly LONG, (for many purposes). Especially if using telephoto lenses.

Woops!

But I'm pretty certain that's usually the highest any speedlite would go.

I have to apologize that I am not sure what you mean, (by "highest any speedlite would go").

!/200 is usually sufficient for still subjects, (and hand-held w/ lens shorter than 200mm-EFL), but is not sufficient to freeze action on moving subjects.

So, to me, it is a totally inadequate flash-sync relative to the 1/4000 sync speed I enjoy on the FZ-1000.

And you mentioned "bullets" above ... that needs about 1/50,000sec to "stop" travel, (and "timing" is the most difficult photography challenge).

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

This is precisely what I meant! Might as well shoot with continous light right?

Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes).

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

In its time yes, but I mainly use it for video work and it still does a pretty good job, but I yearn so badly for a GH4, I just can never ever afford it

They should release a GH5 at some point / soon ???

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time, how does it work? How does it know how to trigger X-amount of flashes in such a short space of time?

Is it an easy circuit to implement? Or does it get real complicated with this??

It is simply a (very fast) series of very-short pulses that last the duration of the shutter-curtain travel.

NOTE that if you do not (fully and properly) UNDERSTAND how FOCAL-PLANE shutter work, you need to stop now and study/learn how they work.

Note that a focal-plane shutter, (even @ 1/8000sec is really only 1/200 or 250sec).  To understand flash sync, you have to understand how they work, (and why 1/200-250 is their "native" flash sync speed).

You don't need to know "how" they work, just that the difference is that in "normal" mode there is (ONE) single (very BRIGHT/POWERFUL) flash, (duration between 1/1000 to 1/50,000sec), and in HSS mode there is a series of continuous pulses for, (a much longer) 1/200 sec.  And NOTE that even if camera is shooting at 1/8000sec, the flash duration is required to be 1/200sec w/ focal-plane shutter.

Sigh...you don't understand how long I have been waiting for a modern digital SLR to carry a Global Shutter sensor, I am absolutely sick and tired of the Rolling Shutter effect! I do a lot of videowork by the way

Also does it only need the electrical short from the camera to lit the LEDs??

I think that is a yes ...

Just so I am not confused, does this electrical short trigger something in the flash device to make the flash happen?

Yes, the capacitor is charged to 300-500vdc and then "discharges" though an "arc".

I'm so stupid, how can I forget this...of course it does this! But sending 300-500volts to discharge in the flashtube is a hellalot, why doesn't it ever blow out the tube?

The flash-tubes do get "hot", but not usually as hot as a conventional incandescent, (or halogen) bulb.

But partially because the duration is indeed so "short". As long as there is time between shots, it can cool off somewhat.

Or is this electrical short the actual "electrical power" that lights up the LEDs??

Well, it is an "arc" .... like LIGHTNING. It literally is a tiny "lightning" strike/arc confined within the tube. It puts out a LOT of light, for a VERY SHORT duration, (less than 1/1000sec and can be as short as 1/50,000sec.).

Good explanation! A good description of telling someone another way tot die in the fastest way possible, hahaha

I ask all this because like I probably implied in my previous posts, could one theoretically replace a flashtube with a standard lightbulb of the same wattage and still get the same results??

Absolutely not ... they are totally different in that the (xenon) tube is an ARC, (a very FAST/SHORT duration arc -- from a 300-500v charged capacitor).

In this case I would like to ask, can a xenon Flashtube work as a continuous light, yes or no?

Absolutely NOT ... No Way ... not even close to the same.

Is it because if 300-500volts were continually sent to the tube for a few seconds, it would explode?

Well, yeah, it probably would because it was not designed for that duty-cycle.

So you saying Xenon tube or Flash tubes were ever ONLY designed to emit light for very short periods of time??

Well, for (still) photographic purposes YES.

But I think there are indeed continuous "arc" type bulbs.

NOTE that HID headlights for CARS/AUTOS are now coming out, and they use an electrical "arc" to generate their light.

So let me get this straight, Flashtubes are a type of Xenon lamps that can't last for no more than a second whereas a Xenon headlight is another type that can work as continuous light??

Well ... I think that is a "yes". The secret to them both is that they generate light from an "arc".

If you know anything about the old WW2 "searchlights" which were used to illuminate enemy bombers up to 20,000' high.

These were then sold as war-surplus and used to attract people to "grand-openings" and other events. Note that they could be seen for many-many-many miles away and people would rush to them to see what was "happening".

Very very interesting piece of history there! Kind off answers a minor question of mine from years ago when I was younger

They used carbon-rods and a very high voltage (and CURRENT) to generate a "arc" so was also very bright, (enough to reach 20,000'+).

Either way, if the Flashtube was given lower voltage, would it simply not light up? Or it will light up but at lower brightness??

It won't "fire" (arc) at less than the 300-500vdc.

Have you ever seen a "small" lighting strike ... they are all big and bright and LOUD.

I have...it sometimes scares me

Because it was my understanding that flashtubes vs lightbulbs are "very different beasts".

Absolutely YES !!! (very different)

I am beginning to understand this more and more thank you to all of you, much grateful!

Well, it does not seem like you understand it very well, but you sorta have to be an engineer/technician to fully understand the technology, (especially the "cut-off" circuitry which can be even more complex). This (cut-off) circuitry must actually STOP the ARC after it starts. It is like stopping a lighting-strike after it starts. Quite amazing.

I worked on X-Ray equipment for 20 years, and we used that same technology to "time" an X-Ray pulse. (albeit at voltages up to 150,000 volts, instead of 300-500).

YES ... I am still alive so "learned" to be VERY CAREFUL, (w/ 150KV).

But you can be dead even from the charged capacitor @ 300-500vdc.

THIS! I am sooo glad you've mentioend this...because out of all the reading and researching this is the first time I've ever read about a "cut-off" circuity!

Yes ... the normal "full-discharge" cycle from a fully charged capacitor is usually about 1/1000sec.

BUT with "auto" and "TTL" controlled strobes the flash can be stopped @ 1/10,000th or even 1/50,000th sec when it is determined the sensor has received enough light for proper exposure.

Wow...that is bloody fast! How on earth do you control light i.e. to start and stop at such a speed and with such precision???

Evidently very easy, (or at least easy enough), there has been "auto" type strobes since the 70's. The Vivitar 283 was one of the earliest and MOST POPULAR "auto" strobe. It was introduced in 1970 and remained in production for over 30 years. It was extremely popular and sold over 3 MILLION by 1973. (I had a couple of them)

Its last incarnation was the 285 and had a "zoom" head for higher power /w telephoto lenses. (the original 283 was designed for a 28mm lens)

BTW, the original 283/285 had a 250v trigger voltage so you can NOT plug it into a "digital" camera, (w/out an adapter to isolate the 250vdc).

Vivitar must've have certainly made a lot of money based on this fact alone. It's a shame its current products are produced in China and its originators have passed away

Yep, it was the most popular strobe for many years.

But I repeat again, DON'T use one on digital if you find an "old" one because they had 250vdc on the contacts and will blow the digital cameras w/ SCR/TRIACS.

Okay okay I promise...I won't use one on a digital camera (however the chances of ever getting one is extremely slim)!

Actually they are very common in pawn shops or ebay because there were so very MANY of them produced, (for many years).

Looks like I'm going to have to avoid them like the plague!

They do have "isolation" hot-shoes, but I personally would not trust them.

The original intention of the Vivitar 283/285 was to mount directly in hot-shoe, (but 250vdc is too "hot" for digital cameras).

I'm sorry

So that means there really is something that stops the electrical circuit going into the tube from the capacitor!

Yes ... it used to be done by a "reverse" discharge of a separate capacitor to a SCR which stops the discharging of the main capacitor through the (xenon) tube.

This is something very new to me now and I'm glad to know about it, I've never heard of "reverse discharge"!

How does it work?? We all know now how discharge works in such device but to go the polar opposite...and with great accuracy...how does one go about going this???

Again, evidently quite easily since it was indeed being done for a long long time.

The technical term is "Forced Commutation".

http://www.electronicshub.org/scr-turn-off-methods/

https://www.pantechsolutions.net/power-electronics/introduction-of-forced-commutation-class-a-b-c-d-e

Now this is becoming more clear, although I really don't understand it much

Is it quite easy to create and implement? Theoretically, could it be used in my LED Ring Flash perhaps??

Absolutely NOT ... it is not at all the same/similar technology.

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Waaahhh...but how does it know when to stop the flash?

It simply stops when the capacitor storage is empty.

It is like a lake with a "dam" ... bust the dam and ALL the water drains out.

In "manual" strobes, Igniting the "arc" ionizes the gas and it becomes an equivalent "short" until all the power is dissipated, (unless artificially stopped as "auto" strobes do).

The bigger the lake, (capacitor size), the longer it will take to drain.  But even the biggest strobes usually do it in less than 1/1000 sec. (but some really "biggest" can take to 1/750-500sec).

Another thing I am trying to understand with this as well is the timings...does it shut off as soon as the shutter contact is made? or a tiiiinyyy bit after the contact??

It "starts" with the first contact, which fires the main SCR/TRIAC, to start the discharge of the main capacitor.

Then there is a light sensor on either the flash itself, or in the camera if TTL, and that determines when sufficient light has hit the subject, (and bounced back to the sensor/TTL).

WHEN sufficient light has hit the subject, it fires the "cut-off" SCR/TRIAC and the flash is immediately stopped/extinguished by stopping the discharge of the main capacitor.

Note that first/earlier auto strobes used to stop the arc by "shorting" the remaining charge of the capacitor away from the flash-tube. BUT ... that meant that the capacitor had to "fully" recharge every time, (because it had been "discharged" by the "shorting" circuit). That meant a "time" was required before the flash could be used again because it had to "fully" recharge each time, (because it had been "fully" discharged).

With the later "forced-commutation" design, the capacitor retained the remaining charge and thus could often be immediately fired again with the remaining charge, (or would recharge faster).

BTW: I have not worked in electronics for several years. It is possible that there are newer "switching" devices that do not require the "forced commutation" design.

BUT ... the THEORY is still the same. The flash is started by the "contacts" in the camera, and then an auto sense device, (now usually TTL in camera), determines the sufficient amount of light, and then (immediately) STOPS the light output, (in as short as 1/50,000sec if "close" range subject).

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

Ahhh, this is where it gets interesting again! So you saying this is done by Positive Pulses you get in a waveform? This was something that was discussed previous in this topic. Or am I wrong?

How does it know when to stop at 1/1000th of a second?

It naturally stops when the power is dissipated, (lake is drained).

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

I had to wonder about life the past three days, got lost a long the way, this is the reason why it took me until now to make a reply

I don't want to talk about "life" ... I am going through the absolute worse period I have ever gone through and I question every day if it is worth continuing.

I met a lady a year ago who has saved my life by telling me that what I was contemplating is a "permanent solution to a temporary problem" and I try to remember that every day.

markkuk Contributing Member • Posts: 733
Re: Maybe not the best idea

OmarAl wrote:

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time

HSS is not useful for stopping quickly moving objects. It's for fill-in flash in bright daylight. For motion-freezing shots, use normal flash in dark environment.

PS. There seems to be something wrong with the "Delete" key in your computer. Please fix it so you don't include every previous message in the thread in your posts.

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PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

markkuk wrote:

OmarAl wrote:

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time

HSS is not useful for stopping quickly moving objects. It's for fill-in flash in bright daylight.

True ... but because of its inherent design, only low-power (GN) and thus useful only for relatively short-range subjects, (compared to the much further fill-flash range of normal-full power).

In many ways HSS is a gimmick and not a true replacement to the value of a higher native flash-sync speed.  (like 1/4000sec on FZ-1000)

For motion-freezing shots, use normal flash in dark environment.

PS. There seems to be something wrong with the "Delete" key in your computer. Please fix it so you don't include every previous message in the thread in your posts.

OP OmarAl New Member • Posts: 21
Re: Maybe not the best idea

Woops!

But I'm pretty certain that's usually the highest any speedlite would go.

I have to apologize that I am not sure what you mean, (by "highest any speedlite would go").

!/200 is usually sufficient for still subjects, (and hand-held w/ lens shorter than 200mm-EFL), but is not sufficient to freeze action on moving subjects.

So, to me, it is a totally inadequate flash-sync relative to the 1/4000 sync speed I enjoy on the FZ-1000.

And you mentioned "bullets" above ... that needs about 1/50,000sec to "stop" travel, (and "timing" is the most difficult photography challenge).

Sorry if I wasn't clear on that matter, I'm probably not very good at my wordings, but basically speedlites on a DSLR would only allow you to go as high as 1/200th shutter speed, and this being due to the nature of the focal-plane shutter. This si what I meant, I hope it is clearer now?

Yes 1/200 is generally good for stills, like modeling with fineee ladies

When I said "bullet-time" I was referring to the Matrix films where they go into extremely slow-motion shots

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

This is precisely what I meant! Might as well shoot with continous light right?

Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes).

Because 1/200 shutter and flash sychronised for it are made for eachother

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

In its time yes, but I mainly use it for video work and it still does a pretty good job, but I yearn so badly for a GH4, I just can never ever afford it

They should release a GH5 at some point / soon ???

They are, in a few months I believe and I cannot wait!

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time, how does it work? How does it know how to trigger X-amount of flashes in such a short space of time?

Is it an easy circuit to implement? Or does it get real complicated with this??

It is simply a (very fast) series of very-short pulses that last the duration of the shutter-curtain travel.

NOTE that if you do not (fully and properly) UNDERSTAND how FOCAL-PLANE shutter work, you need to stop now and study/learn how they work.

Note that a focal-plane shutter, (even @ 1/8000sec is really only 1/200 or 250sec). To understand flash sync, you have to understand how they work, (and why 1/200-250 is their "native" flash sync speed).

You don't need to know "how" they work, just that the difference is that in "normal" mode there is (ONE) single (very BRIGHT/POWERFUL) flash, (duration between 1/1000 to 1/50,000sec), and in HSS mode there is a series of continuous pulses for, (a much longer) 1/200 sec. And NOTE that even if camera is shooting at 1/8000sec, the flash duration is required to be 1/200sec w/ focal-plane shutter.

In regards to the HSS mode and its ability to set off a series of continuous pulses, how it that achieved? I assume it is taking a full power flash set for 1/200 or 250 and breaking it down to a series of small flashes (although when I'm doing it it still looks like one big flash to me), is it somesort of chip/timer that's programming this? Or just clever circuity? Is it i simpler than I think??

Looks like I'm going to have to avoid them like the plague!

They do have "isolation" hot-shoes, but I personally would not trust them.

The original intention of the Vivitar 283/285 was to mount directly in hot-shoe, (but 250vdc is too "hot" for digital cameras).

I think now this has been made very clear, to the point that I would remember is subconsciously when I'm faced with this danger

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Waaahhh...but how does it know when to stop the flash?

It simply stops when the capacitor storage is empty.

It is like a lake with a "dam" ... bust the dam and ALL the water drains out.

In "manual" strobes, Igniting the "arc" ionizes the gas and it becomes an equivalent "short" until all the power is dissipated, (unless artificially stopped as "auto" strobes do).

The bigger the lake, (capacitor size), the longer it will take to drain. But even the biggest strobes usually do it in less than 1/1000 sec. (but some really "biggest" can take to 1/750-500sec).

But there is no capacitor in the LED Ring Flash, it's just a circuit with some wires connected to the battery holder.

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

Ahhh, this is where it gets interesting again! So you saying this is done by Positive Pulses you get in a waveform? This was something that was discussed previous in this topic. Or am I wrong?

How does it know when to stop at 1/1000th of a second?

It naturally stops when the power is dissipated, (lake is drained).

So that means the Flash duration is longer and is always flashing at full power?

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

I had to wonder about life the past three days, got lost a long the way, this is the reason why it took me until now to make a reply

I don't want to talk about "life" ... I am going through the absolute worse period I have ever gone through and I question every day if it is worth continuing.

I met a lady a year ago who has saved my life by telling me that what I was contemplating is a "permanent solution to a temporary problem" and I try to remember that every day.

Ohhh I don't think you are doing any worse than I am...I'm unemployed for starters!

That lady probably has said one of the best lines ever for such situations, I might even used that for a film It'll probably be a good idea to pay that lady a visit one day

PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

OmarAl wrote:

Woops!

But I'm pretty certain that's usually the highest any speedlite would go.

I have to apologize that I am not sure what you mean, (by "highest any speedlite would go").

!/200 is usually sufficient for still subjects, (and hand-held w/ lens shorter than 200mm-EFL), but is not sufficient to freeze action on moving subjects.

So, to me, it is a totally inadequate flash-sync relative to the 1/4000 sync speed I enjoy on the FZ-1000.

And you mentioned "bullets" above ... that needs about 1/50,000sec to "stop" travel, (and "timing" is the most difficult photography challenge).

Sorry if I wasn't clear on that matter, I'm probably not very good at my wordings, but basically speedlites on a DSLR would only allow you to go as high as 1/200th shutter speed, and this being due to the nature of the focal-plane shutter. This si what I meant, I hope it is clearer now?

It seems like you may be familiar with the focal-plane shutter operation, (which most photographers are NOT). So you are ahead of the game in that respect.

Yes 1/200 is generally good for stills, like modeling with fineee ladies

I (tried) a shoot once with an Australian band ... who was very jovial and "jumping" around all the time. (would not hold there "heads" still)

The camera I was using had a max flash-sync of 1/60, (which was faster than the original FP shutters which had a 1/30 max). But the shoot was a disaster because there was at least one persons head blurred in every shot because they would not hold still.

So the new limits of 1/200 - 250 is certainly much better than it used to be back in the '60's & '70's.

When I said "bullet-time" I was referring to the Matrix films where they go into extremely slow-motion shots

In addition to a short-duration strobe, "TIMING" is the most critical and specialized for "bullet" shots.

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

This is precisely what I meant! Might as well shoot with continous light right?

Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes).

Because 1/200 shutter and flash sychronised for it are made for eachother

Well ... yes ... HSS strobes are indeed made for FP shutters.

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

In its time yes, but I mainly use it for video work and it still does a pretty good job, but I yearn so badly for a GH4, I just can never ever afford it

They should release a GH5 at some point / soon ???

They are, in a few months I believe and I cannot wait!

Well, I was eagerly awaiting for a FZ-1000 upgrade ... but disappointed in the FZ-2500 for several reasons, (and will probably not be getting it -- will wait for possibly the "next" FZ upgrade).

So hope the GH5 is indeed a major "upgrade" in areas that matter.

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time, how does it work? How does it know how to trigger X-amount of flashes in such a short space of time?

Is it an easy circuit to implement? Or does it get real complicated with this??

It is simply a (very fast) series of very-short pulses that last the duration of the shutter-curtain travel.

NOTE that if you do not (fully and properly) UNDERSTAND how FOCAL-PLANE shutter work, you need to stop now and study/learn how they work.

Note that a focal-plane shutter, (even @ 1/8000sec is really only 1/200 or 250sec). To understand flash sync, you have to understand how they work, (and why 1/200-250 is their "native" flash sync speed).

You don't need to know "how" they work, just that the difference is that in "normal" mode there is (ONE) single (very BRIGHT/POWERFUL) flash, (duration between 1/1000 to 1/50,000sec), and in HSS mode there is a series of continuous pulses for, (a much longer) 1/200 sec. And NOTE that even if camera is shooting at 1/8000sec, the flash duration is required to be 1/200sec w/ focal-plane shutter.

In regards to the HSS mode and its ability to set off a series of continuous pulses, how it that achieved? I assume it is taking a full power flash set for 1/200 or 250 and breaking it down to a series of small flashes (although when I'm doing it it still looks like one big flash to me), is it somesort of chip/timer that's programming this? Or just clever circuity? Is it i simpler than I think??

Well ... yes even 1/200 can seem extremely "fast" to our eyes. But would not be fast enough for "moving" subjects, (especially w/ tele lenses where motion is magnified).

And even though I am an electronic-engineer, I have not yet studied a schematic of HSS strobe. So I can imagine several methods they might use, I am not sure which they have chosen. (If you want to send a schematic to me, I can probably be more definitive.)

But I can say the strobes must be extremely fast and consistent to avoid "banding" in the final image.

Looks like I'm going to have to avoid them like the plague!

They do have "isolation" hot-shoes, but I personally would not trust them.

The original intention of the Vivitar 283/285 was to mount directly in hot-shoe, (but 250vdc is too "hot" for digital cameras).

I think now this has been made very clear, to the point that I would remember is subconsciously when I'm faced with this danger

Yep ... don't forget it ... It only takes "once" to blow the SCR/TRIAC within the "digital" camera, (where it once was just a mechanical "switch" similar to simply touching two-wires together and thus voltage did not matter).

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Waaahhh...but how does it know when to stop the flash?

It simply stops when the capacitor storage is empty.

It is like a lake with a "dam" ... bust the dam and ALL the water drains out.

In "manual" strobes, Igniting the "arc" ionizes the gas and it becomes an equivalent "short" until all the power is dissipated, (unless artificially stopped as "auto" strobes do).

The bigger the lake, (capacitor size), the longer it will take to drain. But even the biggest strobes usually do it in less than 1/1000 sec. (but some really "biggest" can take to 1/750-500sec).

But there is no capacitor in the LED Ring Flash, it's just a circuit with some wires connected to the battery holder.

True ... no capacitor in LED, (unless a very "small" one that is part of a "timing" circuit to simply turn power on/off to the LEDS. But a capacitor for that purpose is NOTHING like a very "BIG" one being used for "storage" purposes and indeed the primary component in a strobe.

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

Ahhh, this is where it gets interesting again! So you saying this is done by Positive Pulses you get in a waveform? This was something that was discussed previous in this topic. Or am I wrong?

How does it know when to stop at 1/1000th of a second?

It naturally stops when the power is dissipated, (lake is drained).

So that means the Flash duration is longer and is always flashing at full power?

Well, flash duration is all relative. Even 1/200 can seem fast/short in some context. But very long compared to 1/1000 and MUCH longer compared to 1/10,000 or 1/50,000.

To understand the (short) duration, you have to understand the "ARCING" concept of the strobe. When the "arc" is initiated, the gas within the tube is "IONIZED" and becomes a direct "short" which will (extremely) quickly drain the capacitor, (drain the lake of water if the "dam" is complexly broken).

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

I had to wonder about life the past three days, got lost a long the way, this is the reason why it took me until now to make a reply

I don't want to talk about "life" ... I am going through the absolute worse period I have ever gone through and I question every day if it is worth continuing.

I met a lady a year ago who has saved my life by telling me that what I was contemplating is a "permanent solution to a temporary problem" and I try to remember that every day.

Ohhh I don't think you are doing any worse than I am...I'm unemployed for starters!

Well, unemployed is not good ... how old are you and what work have you prior done ???   (education ???)

What are you looking for, you seem like an intelligent person ???

Where do you live ???

That lady probably has said one of the best lines ever for such situations, I might even used that for a film It'll probably be a good idea to pay that lady a visit one day

I was married to my high-school sweetheart for 44 years and she died.

I then met another lady and life was wonderful again, she loved me deeply.  We went dancing 5/nites-week, theater, moves, etc. and sex 2-3x/day, (and I am 70yo).  She told me she loved me 100x/day ...

She went to see her kids one day, walked in the door, DID NOT SAY SHE DIDN'T "LOVE" ME --- just said "Kids Don't Like You ... GET OUT .. NOW !!!"

It has been over a year ago and my head is still spinning, she has still never said she does not love me, she admits she is MISERABLE and MISSES me .. but that her "kids" are "More Important" so she has created an artificial wall between us.

I actually am doing "great" ... I have "lived" with another lady for over a year, but do not love her, and have 4 others that want to "marry" me ... so I should not feel the way I do.

But I still deeply love the other lady and confused that she has chosen to be (admittedly) unhappy while she lives alone but maintains the artificial wall.

OP OmarAl New Member • Posts: 21
Re: Maybe not the best idea

Hello PhotoTeach2! Long time no speak!

Belated Merry Christmas and a Happy New Year!

So sorry if it has taken me this long to respond back, the time were we last left off I became incredibly busy trying to snatch up every possible job and was abroad in the Philippines for a whole month and only got back a few weeks ago!

So please don't think I have forgotten here or abandoned you!

PhotoTeach2 wrote:

OmarAl wrote:

Woops!

But I'm pretty certain that's usually the highest any speedlite would go.

I have to apologize that I am not sure what you mean, (by "highest any speedlite would go").

!/200 is usually sufficient for still subjects, (and hand-held w/ lens shorter than 200mm-EFL), but is not sufficient to freeze action on moving subjects.

So, to me, it is a totally inadequate flash-sync relative to the 1/4000 sync speed I enjoy on the FZ-1000.

And you mentioned "bullets" above ... that needs about 1/50,000sec to "stop" travel, (and "timing" is the most difficult photography challenge).

Sorry if I wasn't clear on that matter, I'm probably not very good at my wordings, but basically speedlites on a DSLR would only allow you to go as high as 1/200th shutter speed, and this being due to the nature of the focal-plane shutter. This si what I meant, I hope it is clearer now?

It seems like you may be familiar with the focal-plane shutter operation, (which most photographers are NOT). So you are ahead of the game in that respect.

Indeed I am, but not at the greatest detail but a little research can go a long way. Focal Plane shutters are fine, they've been around for so long that flash equipment are built around them and to resolve its "limitations".

Yes 1/200 is generally good for stills, like modeling with fineee ladies

I (tried) a shoot once with an Australian band ... who was very jovial and "jumping" around all the time. (would not hold there "heads" still)

The camera I was using had a max flash-sync of 1/60, (which was faster than the original FP shutters which had a 1/30 max). But the shoot was a disaster because there was at least one persons head blurred in every shot because they would not hold still.

So the new limits of 1/200 - 250 is certainly much better than it used to be back in the '60's & '70's.

That's very interesting, surely 1/30 or 1/60 shutter with flash sync can keep a moving object still, I photograph at nightclubs/bars on weekends and I can usually get good images at slower shutter speeds.

When I said "bullet-time" I was referring to the Matrix films where they go into extremely slow-motion shots

In addition to a short-duration strobe, "TIMING" is the most critical and specialized for "bullet" shots.

Absolutely!

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

This is precisely what I meant! Might as well shoot with continous light right?

Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes).

Because 1/200 shutter and flash sychronised for it are made for eachother

Well ... yes ... HSS strobes are indeed made for FP shutters.

Indeed.

However going back on your previous post of "Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes)." were you referring to the idea that strobes and speedlites in High-Sync Speed mode is basically trying to simulate continuous light in order to expose the sensor/film while a slit curtain glides through it??

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

In its time yes, but I mainly use it for video work and it still does a pretty good job, but I yearn so badly for a GH4, I just can never ever afford it

They should release a GH5 at some point / soon ???

They are, in a few months I believe and I cannot wait!

Well, I was eagerly awaiting for a FZ-1000 upgrade ... but disappointed in the FZ-2500 for several reasons, (and will probably not be getting it -- will wait for possibly the "next" FZ upgrade).

So hope the GH5 is indeed a major "upgrade" in areas that matter.

Just looking it up, hasn't the FZ-1000 been around for a couple of years? I'm sure you can get it now.

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time, how does it work? How does it know how to trigger X-amount of flashes in such a short space of time?

Is it an easy circuit to implement? Or does it get real complicated with this??

It is simply a (very fast) series of very-short pulses that last the duration of the shutter-curtain travel.

NOTE that if you do not (fully and properly) UNDERSTAND how FOCAL-PLANE shutter work, you need to stop now and study/learn how they work.

Note that a focal-plane shutter, (even @ 1/8000sec is really only 1/200 or 250sec). To understand flash sync, you have to understand how they work, (and why 1/200-250 is their "native" flash sync speed).

You don't need to know "how" they work, just that the difference is that in "normal" mode there is (ONE) single (very BRIGHT/POWERFUL) flash, (duration between 1/1000 to 1/50,000sec), and in HSS mode there is a series of continuous pulses for, (a much longer) 1/200 sec. And NOTE that even if camera is shooting at 1/8000sec, the flash duration is required to be 1/200sec w/ focal-plane shutter.

In regards to the HSS mode and its ability to set off a series of continuous pulses, how it that achieved? I assume it is taking a full power flash set for 1/200 or 250 and breaking it down to a series of small flashes (although when I'm doing it it still looks like one big flash to me), is it somesort of chip/timer that's programming this? Or just clever circuity? Is it i simpler than I think??

Well ... yes even 1/200 can seem extremely "fast" to our eyes. But would not be fast enough for "moving" subjects, (especially w/ tele lenses where motion is magnified).

And even though I am an electronic-engineer, I have not yet studied a schematic of HSS strobe. So I can imagine several methods they might use, I am not sure which they have chosen. (If you want to send a schematic to me, I can probably be more definitive.)

But I can say the strobes must be extremely fast and consistent to avoid "banding" in the final image.

I think this is where I might have to start a new topic specifically on the matter, I have been looking high and low on how HSS is achieved, not a schematic, or even a patent for it! However if I saw one for HSS I wouldn't be able to tell in the first place

You talk about imagining methods they could use, what do you think one could be? Do you know where I could find schematics for HSS??

Looks like I'm going to have to avoid them like the plague!

They do have "isolation" hot-shoes, but I personally would not trust them.

The original intention of the Vivitar 283/285 was to mount directly in hot-shoe, (but 250vdc is too "hot" for digital cameras).

I think now this has been made very clear, to the point that I would remember is subconsciously when I'm faced with this danger

Yep ... don't forget it ... It only takes "once" to blow the SCR/TRIAC within the "digital" camera, (where it once was just a mechanical "switch" similar to simply touching two-wires together and thus voltage did not matter).

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Waaahhh...but how does it know when to stop the flash?

It simply stops when the capacitor storage is empty.

It is like a lake with a "dam" ... bust the dam and ALL the water drains out.

In "manual" strobes, Igniting the "arc" ionizes the gas and it becomes an equivalent "short" until all the power is dissipated, (unless artificially stopped as "auto" strobes do).

The bigger the lake, (capacitor size), the longer it will take to drain. But even the biggest strobes usually do it in less than 1/1000 sec. (but some really "biggest" can take to 1/750-500sec).

But there is no capacitor in the LED Ring Flash, it's just a circuit with some wires connected to the battery holder.

True ... no capacitor in LED, (unless a very "small" one that is part of a "timing" circuit to simply turn power on/off to the LEDS. But a capacitor for that purpose is NOTHING like a very "BIG" one being used for "storage" purposes and indeed the primary component in a strobe.

Of course, it needs more POWER!

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

Ahhh, this is where it gets interesting again! So you saying this is done by Positive Pulses you get in a waveform? This was something that was discussed previous in this topic. Or am I wrong?

How does it know when to stop at 1/1000th of a second?

It naturally stops when the power is dissipated, (lake is drained).

So that means the Flash duration is longer and is always flashing at full power?

Well, flash duration is all relative. Even 1/200 can seem fast/short in some context. But very long compared to 1/1000 and MUCH longer compared to 1/10,000 or 1/50,000.

To understand the (short) duration, you have to understand the "ARCING" concept of the strobe. When the "arc" is initiated, the gas within the tube is "IONIZED" and becomes a direct "short" which will (extremely) quickly drain the capacitor, (drain the lake of water if the "dam" is complexly broken).

Ahhh I think I am beginning to understand this, because disposable cameras still uses capacitors, albeit a small one, this is the main contributing factor for its flash duration???

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

I had to wonder about life the past three days, got lost a long the way, this is the reason why it took me until now to make a reply

I don't want to talk about "life" ... I am going through the absolute worse period I have ever gone through and I question every day if it is worth continuing.

I met a lady a year ago who has saved my life by telling me that what I was contemplating is a "permanent solution to a temporary problem" and I try to remember that every day.

Ohhh I don't think you are doing any worse than I am...I'm unemployed for starters!

Well, unemployed is not good ... how old are you and what work have you prior done ??? (education ???)

What are you looking for, you seem like an intelligent person ???

Where do you live ???

Well, I'm in my late 20's, and I am a university graduate in Film & Television Production from London, and I do jobs when I'm required so like photographing at a club on a weekend every week, and only been called recently by my previously company to do some filming for their basketball games, and of course the odd message/call asking if I am available to do this and that of the same thing, but nothing that will help get a place of my own, just able to pay for my mobile phone bills, I still live with my parents/family.

I am after Video Editing and Videography jobs and maybe Photography, looking and applying most of my time but constantly rejected, mainly because my showreel only has old work, no longer a high standard, and basically not up to scratch. I desperately want a new camera (Panasonic GH4) where I can increase my quality of work, I am real far behind and I believe this is my solution, hence why I am doing odd jobs but can never get enough to save properly to buy one as I need to feed myself a lot

That lady probably has said one of the best lines ever for such situations, I might even used that for a film It'll probably be a good idea to pay that lady a visit one day

I was married to my high-school sweetheart for 44 years and she died.

I then met another lady and life was wonderful again, she loved me deeply. We went dancing 5/nites-week, theater, moves, etc. and sex 2-3x/day, (and I am 70yo). She told me she loved me 100x/day ...

She went to see her kids one day, walked in the door, DID NOT SAY SHE DIDN'T "LOVE" ME --- just said "Kids Don't Like You ... GET OUT .. NOW !!!"

It has been over a year ago and my head is still spinning, she has still never said she does not love me, she admits she is MISERABLE and MISSES me .. but that her "kids" are "More Important" so she has created an artificial wall between us.

I actually am doing "great" ... I have "lived" with another lady for over a year, but do not love her, and have 4 others that want to "marry" me ... so I should not feel the way I do.

But I still deeply love the other lady and confused that she has chosen to be (admittedly) unhappy while she lives alone but maintains the artificial wall.

OP OmarAl New Member • Posts: 21
Re: Maybe not the best idea

Hello PhotoTeach2?

I guess this got a bit much for you to answer??

I hope my unintelligent brain hasn't worn you out!

PhotoTeach2 Forum Pro • Posts: 11,397
Re: Maybe not the best idea

OmarAl wrote:

Hello PhotoTeach2! Long time no speak!

Belated Merry Christmas and a Happy New Year!

So sorry if it has taken me this long to respond back, the time were we last left off I became incredibly busy trying to snatch up every possible job and was abroad in the Philippines for a whole month and only got back a few weeks ago!

So please don't think I have forgotten here or abandoned you!

PhotoTeach2 wrote:

OmarAl wrote:

Woops!

But I'm pretty certain that's usually the highest any speedlite would go.

I have to apologize that I am not sure what you mean, (by "highest any speedlite would go").

!/200 is usually sufficient for still subjects, (and hand-held w/ lens shorter than 200mm-EFL), but is not sufficient to freeze action on moving subjects.

So, to me, it is a totally inadequate flash-sync relative to the 1/4000 sync speed I enjoy on the FZ-1000.

And you mentioned "bullets" above ... that needs about 1/50,000sec to "stop" travel, (and "timing" is the most difficult photography challenge).

Sorry if I wasn't clear on that matter, I'm probably not very good at my wordings, but basically speedlites on a DSLR would only allow you to go as high as 1/200th shutter speed, and this being due to the nature of the focal-plane shutter. This si what I meant, I hope it is clearer now?

It seems like you may be familiar with the focal-plane shutter operation, (which most photographers are NOT). So you are ahead of the game in that respect.

Indeed I am, but not at the greatest detail but a little research can go a long way. Focal Plane shutters are fine,

They are absolutely NOT "fine" ... they were simply the only alternative at the time, (60+yrs ago). Nikon tried "electronic" shutters about 10yrs ago in the D70/D1x genre of cameras -- but their were some problems and they went back to FP.

The dream is of "global" shutters but they are still in the future.

The FZ-1000 has a CHOICE of either a "leaf" shutter or "electronic" shutters.

The leaf-shutter allows up to 1/4000 flash sync, (while the electronic allows up to 1/32,000 but w/out flash).

Back in film days, I used to prefer "rangefinder" type cameras because they had leaf-shutters, (albeit them limited to 1/500).

they've been around for so long that flash equipment are built around them and to resolve its "limitations".

NO again ... HSS is mainly a "gimmick" which is useful for limited applications due to their reduced power, (GN).

Yes 1/200 is generally good for stills, like modeling with fineee ladies

I (tried) a shoot once with an Australian band ... who was very jovial and "jumping" around all the time. (would not hold there "heads" still)

The camera I was using had a max flash-sync of 1/60, (which was faster than the original FP shutters which had a 1/30 max). But the shoot was a disaster because there was at least one persons head blurred in every shot because they would not hold still.

So the new limits of 1/200 - 250 is certainly much better than it used to be back in the '60's & '70's.

That's very interesting, surely 1/30 or 1/60 shutter with flash sync can keep a moving object still, I photograph at nightclubs/bars on weekends and I can usually get good images at slower shutter speeds.

NO AGAIN ... 1/30-60 is very often NOT sufficient to stop movement, (especially w/ telephoto lenses). I have indeed often been FORCED to shoot @ 1/30-60 but hopefully only w/ WA lenses and "slower" subjects.

But the worse aspect is SUNLIGHT shooting. Even 1/60 requires an f/stop of f/22 @ ISO 125, (f/32 @ 1/30sec). First of all that is a "diffractionally" soft image, but even a GN-60 strobe would only be effective @ <3'.

Note w/ 1/4000sec, I can shoot @ f/2.8 even in SUNlight and get effective range of 20' w/ GN-60 (compared to <3' f/22).

I used to shoot weddings with a GN-200 strobe, (Metz 60-CT4), and thus could get effective fill-flash up to 65' in sunlight.

When I said "bullet-time" I was referring to the Matrix films where they go into extremely slow-motion shots

In addition to a short-duration strobe, "TIMING" is the most critical and specialized for "bullet" shots.

Absolutely!

But that is understandable, in order to flash that many lights in such a short space of time sacrifices has to be made, power is decreased to enable for more speed. Pretty much common sense, right?

Instead of "one" really BRIGHT flash, (that illuminates the entire sensor at one time).

The available power is lowered and stretched out for a long (1/200+sec) and only illuminates "part" of the sensor at each pulse.

This is precisely what I meant! Might as well shoot with continous light right?

Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes).

Because 1/200 shutter and flash sychronised for it are made for eachother

Well ... yes ... HSS strobes are indeed made for FP shutters.

Indeed.

However going back on your previous post of "Well, shooting @ 1/200sec, you essentially are shooting at "continuous" light, (compared to the "action-stopping" 1/1000 to 1/50,000 of strobes)." were you referring to the idea that strobes and speedlites in High-Sync Speed mode is basically trying to simulate continuous light in order to expose the sensor/film while a slit curtain glides through it??

YES ... exactly ... the strobe "duration" has to be 1/200 sec.

You seem to really like this FZ-1000, it worth mentioning that I own a Panasonic GH2

That was a very good (and advanced) camera in its time.

In its time yes, but I mainly use it for video work and it still does a pretty good job, but I yearn so badly for a GH4, I just can never ever afford it

They should release a GH5 at some point / soon ???

They are, in a few months I believe and I cannot wait!

Well, I was eagerly awaiting for a FZ-1000 upgrade ... but disappointed in the FZ-2500 for several reasons, (and will probably not be getting it -- will wait for possibly the "next" FZ upgrade).

So hope the GH5 is indeed a major "upgrade" in areas that matter.

Just looking it up, hasn't the FZ-1000 been around for a couple of years? I'm sure you can get it now.

I am still sticking with the FZ-1000 for now. Sony has a new sensor in their RX100-"V" which has PD-AF and claims to be able to C-AF @ 25fps. So I am waiting for that sensor in my next new camera.

This HSS (High-Sync Speed) has really intrigued me recently, especially due to the fact that it is an essential feature if you want to capture extremely fast action so their frozen in time, how does it work? How does it know how to trigger X-amount of flashes in such a short space of time?

Is it an easy circuit to implement? Or does it get real complicated with this??

It is simply a (very fast) series of very-short pulses that last the duration of the shutter-curtain travel.

NOTE that if you do not (fully and properly) UNDERSTAND how FOCAL-PLANE shutter work, you need to stop now and study/learn how they work.

Note that a focal-plane shutter, (even @ 1/8000sec is really only 1/200 or 250sec). To understand flash sync, you have to understand how they work, (and why 1/200-250 is their "native" flash sync speed).

You don't need to know "how" they work, just that the difference is that in "normal" mode there is (ONE) single (very BRIGHT/POWERFUL) flash, (duration between 1/1000 to 1/50,000sec), and in HSS mode there is a series of continuous pulses for, (a much longer) 1/200 sec. And NOTE that even if camera is shooting at 1/8000sec, the flash duration is required to be 1/200sec w/ focal-plane shutter.

In regards to the HSS mode and its ability to set off a series of continuous pulses, how it that achieved? I assume it is taking a full power flash set for 1/200 or 250 and breaking it down to a series of small flashes (although when I'm doing it it still looks like one big flash to me), is it somesort of chip/timer that's programming this? Or just clever circuity? Is it i simpler than I think??

Well ... yes even 1/200 can seem extremely "fast" to our eyes. But would not be fast enough for "moving" subjects, (especially w/ tele lenses where motion is magnified).

And even though I am an electronic-engineer, I have not yet studied a schematic of HSS strobe. So I can imagine several methods they might use, I am not sure which they have chosen. (If you want to send a schematic to me, I can probably be more definitive.)

But I can say the strobes must be extremely fast and consistent to avoid "banding" in the final image.

I think this is where I might have to start a new topic specifically on the matter, I have been looking high and low on how HSS is achieved, not a schematic, or even a patent for it! However if I saw one for HSS I wouldn't be able to tell in the first place

You talk about imagining methods they could use, what do you think one could be? Do you know where I could find schematics for HSS??

Well, most of Canon and Nikons strobes now support HSS, so the schematic of any of them are, (should be), available ... I just have not researched it.

Basically they have a (continuous) "pulsing" system, (but must also electronically "stop" each individual strobe to conserve power for repeatedly pulsing).

Looks like I'm going to have to avoid them like the plague!

They do have "isolation" hot-shoes, but I personally would not trust them.

The original intention of the Vivitar 283/285 was to mount directly in hot-shoe, (but 250vdc is too "hot" for digital cameras).

I think now this has been made very clear, to the point that I would remember is subconsciously when I'm faced with this danger

Yep ... don't forget it ... It only takes "once" to blow the SCR/TRIAC within the "digital" camera, (where it once was just a mechanical "switch" similar to simply touching two-wires together and thus voltage did not matter).

Then how can I change the flash duration of this little device? It's absolutely horrible (including the discharge)!

You can't ... not to the short pulse of a "strobe" (arc-discharge).

Waaahhh...but how does it know when to stop the flash?

It simply stops when the capacitor storage is empty.

It is like a lake with a "dam" ... bust the dam and ALL the water drains out.

In "manual" strobes, Igniting the "arc" ionizes the gas and it becomes an equivalent "short" until all the power is dissipated, (unless artificially stopped as "auto" strobes do).

The bigger the lake, (capacitor size), the longer it will take to drain. But even the biggest strobes usually do it in less than 1/1000 sec. (but some really "biggest" can take to 1/750-500sec).

But there is no capacitor in the LED Ring Flash, it's just a circuit with some wires connected to the battery holder.

True ... no capacitor in LED, (unless a very "small" one that is part of a "timing" circuit to simply turn power on/off to the LEDS. But a capacitor for that purpose is NOTHING like a very "BIG" one being used for "storage" purposes and indeed the primary component in a strobe.

Of course, it needs more POWER!

Yes ... the normal "storage" capacitors are very big, (and sound like a SHOTGUN when I like to "short" them with a screwdriver to impress the ladies).

Wow...so much information to take in! Really helpful nevertheless!

Before I go into this in more detail, I just would like to quickly ask, with something like a disposable camera flash circuit, of the DIY Flash that I linked previously, do they carry "Force Commutation"? Especially with the case of a disposable camera (simply because the circuity looks small and relatively simple), how is it able to stop the flash? I ask this because it pretty much works exactly like a speedlite and strobe.

They do NOT use forced commutation.

There pulse duration is probably about the normal/natural 1/1000sec. (but maybe shorter because they were not that "powerful" so didn't have the size/capacity of capacitor that would be found in more powerful units, (what would indeed use a very large capacitor).

Ahhh, this is where it gets interesting again! So you saying this is done by Positive Pulses you get in a waveform? This was something that was discussed previous in this topic. Or am I wrong?

How does it know when to stop at 1/1000th of a second?

It naturally stops when the power is dissipated, (lake is drained).

So that means the Flash duration is longer and is always flashing at full power?

Well, flash duration is all relative. Even 1/200 can seem fast/short in some context. But very long compared to 1/1000 and MUCH longer compared to 1/10,000 or 1/50,000.

To understand the (short) duration, you have to understand the "ARCING" concept of the strobe. When the "arc" is initiated, the gas within the tube is "IONIZED" and becomes a direct "short" which will (extremely) quickly drain the capacitor, (drain the lake of water if the "dam" is complexly broken).

Ahhh I think I am beginning to understand this, because disposable cameras still uses capacitors, albeit a small one, this is the main contributing factor for its flash duration???

Yes ... the disposable cameras had smaller capacitors because their flashes were only intended for about GN-30.

So I guess this is what determines the "Flash Duration" right???

Yep ...

This has now been solved for the world to know!

Now that I have told the "secrets", I have to KILL everyone !!!

Hey wait a minute! I thought we were friends??

You will have to decide that AFTER I "kill" you ....

(such is the price that must be paid for "secret / forbidden" knowledge).

Ahhh maaan! Looks like I might have to continue this in the afterlife

We may already be in a "afterlife" ... some say we have had many "before" lives ...

I had to wonder about life the past three days, got lost a long the way, this is the reason why it took me until now to make a reply

I don't want to talk about "life" ... I am going through the absolute worse period I have ever gone through and I question every day if it is worth continuing.

I met a lady a year ago who has saved my life by telling me that what I was contemplating is a "permanent solution to a temporary problem" and I try to remember that every day.

Ohhh I don't think you are doing any worse than I am...I'm unemployed for starters!

Well, unemployed is not good ... how old are you and what work have you prior done ??? (education ???)

What are you looking for, you seem like an intelligent person ???

Where do you live ???

Well, I'm in my late 20's, and I am a university graduate in Film & Television Production from London, and I do jobs when I'm required so like photographing at a club on a weekend every week, and only been called recently by my previously company to do some filming for their basketball games, and of course the odd message/call asking if I am available to do this and that of the same thing, but nothing that will help get a place of my own, just able to pay for my mobile phone bills, I still live with my parents/family.

I am after Video Editing and Videography jobs and maybe Photography, looking and applying most of my time but constantly rejected, mainly because my showreel only has old work, no longer a high standard, and basically not up to scratch. I desperately want a new camera (Panasonic GH4) where I can increase my quality of work, I am real far behind and I believe this is my solution, hence why I am doing odd jobs but can never get enough to save properly to buy one as I need to feed myself a lot

Well, the GH-5 is out now, but you may also be OK w/ FZ-2500.

Both have the new 4K-video features.

That lady probably has said one of the best lines ever for such situations, I might even used that for a film It'll probably be a good idea to pay that lady a visit one day

I was married to my high-school sweetheart for 44 years and she died.

I then met another lady and life was wonderful again, she loved me deeply. We went dancing 5/nites-week, theater, moves, etc. and sex 2-3x/day, (and I am 70yo). She told me she loved me 100x/day ...

She went to see her kids one day, walked in the door, DID NOT SAY SHE DIDN'T "LOVE" ME --- just said "Kids Don't Like You ... GET OUT .. NOW !!!"

It has been over a year ago and my head is still spinning, she has still never said she does not love me, she admits she is MISERABLE and MISSES me .. but that her "kids" are "More Important" so she has created an artificial wall between us.

I actually am doing "great" ... I have "lived" with another lady for over a year, but do not love her, and have 4 others that want to "marry" me ... so I should not feel the way I do.

But I still deeply love the other lady and confused that she has chosen to be (admittedly) unhappy while she lives alone but maintains the artificial wall.

(cheer up)

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