External flash musings

Columbusrat

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I've borrowed a friend's Speedlite 430EX to try on my Canon 250D. They seem to sync OK, but I'm not (yet) getting the results I'd really hope for. I was hoping that being able to have a speed faster than 1/200 sec would make the photos sharper, but...





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It's OK, but if I wanted to crop tightly, it's not quite there. I thought it might be that the extra weight was making me less steady, but on some photos I can't find any area that's spot on.

Now, this was taken with the flash pointing at the subject, with a mesh diffuser, so has issues similar to using with my built-in flash & diffuser. I really need to diffuse/reflect the light, but here is maybe my main issue...

I have dodgy shoulders and I'm not generally very strong (5' tall, arms like sparrow legs, fibromyalgia), so as it is I'm finding the camera/flash combo a bit heavy and cumbersome. Adding something on top of that and I'll feel like I've got the Taj Mahal balanced on top of my camera. And for me, the most important bit of my photography is probably the enjoyment of mooching round the borders and going into quite a Zen-like state. But of course I do still want to get the best photos I can, given my limitations.

So, questions - would sticking some old tights over the flash diffuse the light more and give better results, or would I need to find a way of bouncing it? I know I could build a reflector for my built-in flash, but then I'm limited to no faster than 1/200 sec, and on sunny days I'm not sure the flash freezes the motion sufficiently (if I manage to focus on a flying bug, the wings are a blur). And why isn't my focus quite there, or is it more an effect of the harsh lighting? At hubby's suggestion I did try a wider aperture, but it didn't seem to help - and depth of field of course became more of an issue.

I had wondered about a ring flash, but hubby says they tend to give a more bright flat light - good for identifying details of bugs, but not for artistic shots (I do love bokeh). And I'm not sure if the added weight right at the end of the lens would make it awkward. Are there more compact external flashes that would be compatible with my camera? (Bearing in mind Canon having altered the hotshoe so so anything other than Canon is unlikely to work.) Would a change of body help - are there cameras that allow you to have faster speeds when using the built-in flash? Anything else I could consider?

Oh, one more thing - the time taken for the flash to recharge after a shot is a real pain when I'm trying to photograph a hoverfly that gets into the perfect pose just after I've taken a photo, and then flies off before it's recharged. If anyone has a solution to that that doesn't involve yet more bulky equipment, that would be great!
 
If something in the foreground moves while the shutter is open the background will be under exposed in that area.
So that's what is going on. So simple. Thanks for the explanation John.
Anytime :)

Yet another light related concept that took me an embarrassingly long time to wrap my head around. Me thinks lighting is tough because at a basic level it is not very intuitive.
 
Yet another light related concept that took me an embarrassingly long time to wrap my head around. Me thinks lighting is tough because at a basic level it is not very intuitive.
I'm so glad you said that, because I really do struggle with the lighting aspect of photography!

Hubby is going to get creative with Pringle tubes later, being a far better bodger than me. We have a good supply, saved up all through lockdown for when the local recycling scheme gets going again, but he's hoping he'll get through enough prototypes to need to buy some new ones and eat the contents.

My son would probably be up for digitally printing a diffuser if I found a good pattern.
 
One more thing to consider: some of the more powerful Speedlites accept an external battery pack that does not have to be attached to the camera. It can greatly shorten the recycle time.
 
Yet another light related concept that took me an embarrassingly long time to wrap my head around. Me thinks lighting is tough because at a basic level it is not very intuitive.
I'm so glad you said that, because I really do struggle with the lighting aspect of photography!

Hubby is going to get creative with Pringle tubes later, being a far better bodger than me. We have a good supply, saved up all through lockdown for when the local recycling scheme gets going again, but he's hoping he'll get through enough prototypes to need to buy some new ones and eat the contents.

My son would probably be up for digitally printing a diffuser if I found a good pattern.
Experimenting is the key, keep trying different things until you get the light quality that you want. A Pringles can will work, but I have never been impressed with the light quality from that setup.
 
Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster meaning sharper images. It really matters when shooting higher magnifications.
 
John has already mentioned it but it can take a little bit rethinking when you use a flash.

If you use HSS the shutter opens and the flash starts pulsing it does this until the shutter closes, this means your exposure (the time that light is hitting the subject) is as long as the shutter is open, lets say your camera has a HSS speed of 1/2000 this is 1/2000th of a second.

When you use normal sync (the other non HSS modes, 1st and second curtain) what happens is the flash only fires in one pulse when the shutter has fully opened then the shutter closes. This means the flash fire speed is what controls the exposure length, if your flash is powerful and close to the subject this can be much, much faster eg 1/10000 for example, this then freezes much better the motion that exists in the scene, subject movement and the camera movement from your hands. This leads to much sharper images as a lot of detail loss in macro is from micro movements.

When we shoot macro with a flash the aim is for light to hit the subject for as little a time as possible.
 
Thank you Jarlrmai :-)
 
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Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster
It could be, but it can be as slow as 1/200 sec at full power depending on the flash. I run my flashes at a constant 1/4 power and the duration is somewhere around 1/2000 sec, which is similar for example to the Canon 600 EX-RT at 1/4 power (link).
meaning sharper images. It really matters when shooting higher magnifications.
 
I've started experimenting with a Pringles tube diffractor, but it's early days. However, I wonder if anyone could give an opinion on this photo, please?

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Detail:

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Now, you can see it's individual ocelli, which is pretty much how I define 'in focus'. And they and the pollen grains are the right shape, so motion is presumably frozen. But the sharp edges, e.g. the hairs, and what appear to be hairs in the eye, are bright and 'sparkly' - is this an effect of poorly diffused light, of could it be diffraction because of the small (1/32) depth of field? I don't want to try to fix it with diffusers etc. if they're not actually the cause.

And if it is diffraction, is there a way of avoiding it apart from increasing aperture or doing fancy post-processing?

BTW, this was taken with the built-in flash and fabric diffuser.
 
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More unwanted sparkliness here:



803ddd81fa704a3399f03031af9acbf6.jpg
 
Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster meaning sharper images. It really matters when shooting higher magnifications.
Every time the flash fires it is recording a "time slice" and if there is an motion it will get recorded. HSS is a terrible flash mode if there is any motion at all in the scene -subject and/or camera.
 
Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster meaning sharper images. It really matters when shooting higher magnifications.
Every time the flash fires it is recording a "time slice" and if there is an motion it will get recorded. HSS is a terrible flash mode if there is any motion at all in the scene -subject and/or camera.
What is the difference in the effect of motion on an image as between HSS flash at a shutter speed of 1/2000 sec versus non-HSS flash with a flash pulse length of 1/2000 sec? The "time slice" is the same in both cases. Why would HSS be terrible in this case but non-HSS would not be terrible?
 
Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster meaning sharper images. It really matters when shooting higher magnifications.
Every time the flash fires it is recording a "time slice" and if there is an motion it will get recorded. HSS is a terrible flash mode if there is any motion at all in the scene -subject and/or camera.
What is the difference in the effect of motion on an image as between HSS flash at a shutter speed of 1/2000 sec versus non-HSS flash with a flash pulse length of 1/2000 sec? The "time slice" is the same in both cases. Why would HSS be terrible in this case but non-HSS would not be terrible?
Because when using HSS the shutter speed does not matter. Every time the flash fires a portion of the final exposure is recorded. If there is motion then HSS will show it. The only situation where you would want to use HSS is when there is absolutely no motion.

Think of it in terms of focus stacking video. If you are going to shoot at 30 frames per second and then focus stack six frames then the final shot would represent 1/5 of a second of time (6/30).

If the flash is firing at 1/2000 of a second then that is your "shutter speed".
 
Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster meaning sharper images. It really matters when shooting higher magnifications.
Every time the flash fires it is recording a "time slice" and if there is an motion it will get recorded. HSS is a terrible flash mode if there is any motion at all in the scene -subject and/or camera.
What is the difference in the effect of motion on an image as between HSS flash at a shutter speed of 1/2000 sec versus non-HSS flash with a flash pulse length of 1/2000 sec? The "time slice" is the same in both cases. Why would HSS be terrible in this case but non-HSS would not be terrible?
Because when using HSS the shutter speed does not matter. Every time the flash fires a portion of the final exposure is recorded. If there is motion then HSS will show it. The only situation where you would want to use HSS is when there is absolutely no motion.

Think of it in terms of focus stacking video. If you are going to shoot at 30 frames per second and then focus stack six frames then the final shot would represent 1/5 of a second of time (6/30).

If the flash is firing at 1/2000 of a second then that is your "shutter speed".
And if you are using HSS for 1/2000 sec then that is your shutter speed. What is the difference?
 
Because 1/2000 is not fast enough HSS pulses the flash during the shutter open time, letting it fire at sync makes it fire as far as possible up depending on your flash and proximity this could be 1/10000 or even faster meaning sharper images. It really matters when shooting higher magnifications.
Every time the flash fires it is recording a "time slice" and if there is an motion it will get recorded. HSS is a terrible flash mode if there is any motion at all in the scene -subject and/or camera.
What is the difference in the effect of motion on an image as between HSS flash at a shutter speed of 1/2000 sec versus non-HSS flash with a flash pulse length of 1/2000 sec? The "time slice" is the same in both cases. Why would HSS be terrible in this case but non-HSS would not be terrible?
Because when using HSS the shutter speed does not matter. Every time the flash fires a portion of the final exposure is recorded. If there is motion then HSS will show it. The only situation where you would want to use HSS is when there is absolutely no motion.

Think of it in terms of focus stacking video. If you are going to shoot at 30 frames per second and then focus stack six frames then the final shot would represent 1/5 of a second of time (6/30).

If the flash is firing at 1/2000 of a second then that is your "shutter speed".
And if you are using HSS for 1/2000 sec then that is your shutter speed. What is the difference?
Like I have said several times: With HSS the flash is pulsing while the shutter is open, and every time it fires if there is any motion it will get recorded. Better to have a single pulse of light than dozens if there is any motion at all...

Not gonna get into an endless debate with you. Set your flash to HSS and go out and shoot. Then come back here and ask me how come your photos are not sharp...
 

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