Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

Started May 21, 2012 | Discussions
fabianbono
fabianbono Regular Member • Posts: 190
Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

After a lot of reading of web pages, forums, and with some help from the user OWHK, I successfully modify my HVL-F&S flash of my SONY NEX C3, to provide a PC Port Sync cable to trigger external flash WITHOUT PREFLASH!!!!

And the best is that works no matter the Sony Flash is ON or OFF (Up or Down).

It triggers only on main flash strobe, so is perfect to trigger an external flash, or a wireless trigger.

These are the sources of information I use:

A useful mail sent by OWHK, with detail information about how to get the SYNC signal.

http://nex-hack.blogspot.com.ar/2012/01/about.html
(The base of the circuit to amplify the SYNC signal.)

http://kundweb.netatonce.com/~u23400/Dismount.htm
http://info.xitek.com/product/201203/12-75575.html
(How to disarm the flash unit)

http://forum.xitek.com/forum-viewthread-tid-970489-ordertype-1-highlight-f7s-page-1.html
(The real source of information for the success!!, thanks Google Translate)

The below pictures shows you the pins to use, that is SYNC and GND (OWHK, check that is different from your suggested LGND).

The basic circuit to amplify this signal (and protect camera at same time).

I use all 4,7K Resistor, so use 3 to build 15K, but values not need to be exact.
5K can be up to 10K, and 15K up to 47K.

REMEMBER TO DISCHARGE THE CAPACITOR WITH 1K RESISTOR BEFORE TO WORK WITH THE BOARD.

The point chosen to make the cable connection (better than near 14 pin connector...)

The small box to keep the circuit and cable connection.

Later will take some pictures using this combo, but the test was very successful.

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
madzazulu Senior Member • Posts: 1,311
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

Cool...I assume this manual flash only.

RussellInCincinnati Veteran Member • Posts: 3,201
what would be neat way to get to radio trigger?

This is a nice setup for syncing to a flash via a cable . Wonder how exactly you would connect and arrange a hot shoe that could be strapped to the top of the flash. Into which you could slide a Yongnuo RF-603 remote flash radio transmitter.

ollie_b Regular Member • Posts: 157
Re: what would be neat way to get to radio trigger?
fabianbono
fabianbono OP Regular Member • Posts: 190
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

madzazulu wrote:

Cool...I assume this manual flash only.

Actually, it works in ALL Camera modes, for sure in M mode is the best usage.
SYNC signal is a kind of "shutter pressed" signal, instead of Flash Fire.

RussellInCincinnati wrote:

This is a nice setup for syncing to a flash via a cable. Wonder how exactly you would connect and arrange a hot shoe that could be strapped to the top of the flash. Into which you could slide a Yongnuo RF-603 remote flash radio transmitter.

My first plan was to attach a shoe at HVL-F7S top, but I refuse by now to avoid damage the flash unit. So, only wire the cables inside. And I only use what I have at home this weekend!

I'm searching which radio trigger to use, and the plan is to use a small flash bracket to attach the Wireless TX at side.

I'm researching on Yongnuo RF-603 Wireless Flash Trigger for Canon C1, I think RX can accept my YN560II at the Hot shoe.

I order this bracket, that is useful to attach my YN560II or Wireless TX trigger:

http://www.ebay.com/itm/260790943042?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
madzazulu Senior Member • Posts: 1,311
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

I meant this is only non TTL ?.

j13l Junior Member • Posts: 32
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

Great idea.

But, the use of an opto-isolator would be safer for the camera. (eg MOC3030 + a resistance for LED)
Some flash have high voltages. http://www.botzilla.com/photo/strobeVolts.html

Thank you for your search.

fabianbono
fabianbono OP Regular Member • Posts: 190
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

madzazulu wrote:

I meant this is only non TTL ?.

Yes, this solution for sure is not TTL.
Actually if you look on HVL-F7S specs, is not TTL neither....

And I'm learning from Zack Arias workshops to use full manual solution, so no need TTL, just manual settings.

j13l wrote:

Great idea.

But, the use of an opto-isolator would be safer for the camera. (eg MOC3030 + a resistance for LED)
Some flash have high voltages. http://www.botzilla.com/photo/strobeVolts.html

Thank you for your search.

Yes, I know that, but I built this based on my needs only.

My YN560II is low voltage strobe, and my older flash (a Braun BC31) that use to be high voltage, I already include the optoisolator circuit inside one year ago.
So no risk (for me)!

Every one can improve for sure this solution.

Actually I want to modify some hot shoe to attach in the top of the flash, then an small WLL transmitter can be attached directly on flash body.

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
Smiert Spionam Contributing Member • Posts: 547
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

Nice! Looks great.

The RF-603 is not necessarily the best choice for a trigger, though I really like them. In order to use it as a generic trigger (ie, not attached to a Nikon or Canon body), you have to modify them by adding a resistor. It's not hard to do (I did it, so I can now use my Nikon RF-603s interchangeably with my NEX-7), but it won't work without modification.

Some tips:

http://forums.dpreview.com/forums/readflat.asp?forum=1042&thread=40946611

madzazulu Senior Member • Posts: 1,311
Re: Success PC Port output on HVL-F7S (Sony NEX) without PREFLASH!!!

fabianbono wrote:

madzazulu wrote:

I meant this is only non TTL ?.

Yes, this solution for sure is not TTL.
Actually if you look on HVL-F7S specs, is not TTL neither....

And I'm learning from Zack Arias workshops to use full manual solution, so no need TTL, just manual settings.

I believe it's TTL, manual flash has to have power adjuster. the HVL-F7S doesn't have one. I'm familiar with using manual flash but for shooting event TTL is what I prefer.

electronbee Contributing Member • Posts: 668
Wow, I was going in a totally different direction

I went as far as the other pages, but, too far to be exact. I need to get a logic analyzer for sure now!

Any ways, what it seems to be is that the signal that is used to fire the flash with either the Shadow hot shoe adapter or this mod is coming from the camera, regardless if a flash is present. But, with the exception of no pre-flash.

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 electronbee's gear list:electronbee's gear list
Canon PowerShot S90 Sony Alpha NEX-5N Sony E 18-200mm F3.5-6.3 OSS Voigtlander 15mm F4.5 Super Wide Heliar Sony E 50mm F1.8 OSS +1 more
electronbee Contributing Member • Posts: 668
Use a NTE3041/4N25 as the transistor

It's an optically isolated one in a 6-lead package. Be perfect for this application.

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Arthur Dent hoped and prayed there wasn't an afterlife. Then, realizing the contradiction, he merely hoped there wasn't an afterlife.

  • Douglas Adams, In Literature/Douglas Adams

 electronbee's gear list:electronbee's gear list
Canon PowerShot S90 Sony Alpha NEX-5N Sony E 18-200mm F3.5-6.3 OSS Voigtlander 15mm F4.5 Super Wide Heliar Sony E 50mm F1.8 OSS +1 more
RussellInCincinnati Veteran Member • Posts: 3,201
fabian does your mod suppress Sony flash output?

A few details from fabianbono to pin down.

Firstly, does this convert-Sony-Shutter-Sync-to-standard-hot-shoe-flash-trigger-signal modification suppress the Sony flash output, even when the Sony flash is raised to active position? To be specific, does it suppress the preflash when the Sony flash is raised to "on" position? Separate question, does it suppress the main flash? The latter question relates to a sizable savings of camera battery power, and also perhaps eliminating the need to put a piece of tape over the Sony flash tube if you want to suppress its light.

Secondly, while I understand that the fabianbono mod will send out a trigger signal whether the Sony flash is raised or lowered, under what conditions if any does the wonderful Sony feature of brightening the viewfinder still function?

I.e. are my assumptions correct, that (a) you don't get viewfinder auto-brightening when the Sony flash is lowered and (b) you do get preview auto-brightening when the Sony flash is raised to traditional "on" position?

Thirdly, how long would it take you now to disassemble the little Sony flash, solder in the 2 wires needed, and then put the flash back together?

Fourthly, do you even think you absolutely need the entire Sony flash unit to wire up a trigger? Wonder what would happen if you had a little chunk of circuit board with "fingers" disconnected (except for the 2 connection fingers that have the wires soldered to them, plus the resistors and transistor you need), that you plugged into the Sony flash connector slot. Could that little circuit board if it was somehow insertable and removable still function as a flash trigger? Or does the entire flash need to be plugged in, in order to convince the Nex camera that it's time to send out signals to the top port.

Thanks in advance.

fabianbono
fabianbono OP Regular Member • Posts: 190
Re: fabian does your mod suppress Sony flash output?

Hi Russel, my comments here

RussellInCincinnati wrote:

A few details from fabianbono to pin down.

Firstly, does this convert-Sony-Shutter-Sync-to-standard-hot-shoe-flash-trigger-signal modification suppress the Sony flash output, even when the Sony flash is raised to active position? To be specific, does it suppress the preflash when the Sony flash is raised to "on" position?

The Sony Flash works totally independent of this mod.

It continue working same as original. The mod don't suppress it and normal working is not affected.
Sony flash continue firing preflash.

Separate question, does it suppress the main flash? The latter question relates to a sizable savings of camera battery power, and also perhaps eliminating the need to put a piece of tape over the Sony flash tube if you want to suppress its light.

The mod don't suppress the main flash.
But you can still firing external flash with Sony flash in off position (down).
So it will save battery since no flash firing on camera.

Secondly, while I understand that the fabianbono mod will send out a trigger signal whether the Sony flash is raised or lowered, under what conditions if any does the wonderful Sony feature of brightening the viewfinder still function?

This is the weak point of the mod.
With Sony flash down (off) you will not get the LCD screen brighten up.

This also could affect your AF function, even with AF illumination assistance light.

Issue is to operate the camera on a very dark condition (or no light at all), then I rise up the Sony Flash (to brighten the LCD screen), half press the shutter button to get the AF make focus, then while maintain the half pressed shutter button, down the Sony Flash and then shoot the picture.

On this condition, the only restriction is that you will have available only the value settings of speed and aperture for Sony Flash. Camera will reduce your value available ranges.

I.e. are my assumptions correct, that (a) you don't get viewfinder auto-brightening when the Sony flash is lowered and (b) you do get preview auto-brightening when the Sony flash is raised to traditional "on" position?

(a) your are right, no auto-brightening when the Sony flash is lowered
(b) you are right too.

Thirdly, how long would it take you now to disassemble the little Sony flash, solder in the 2 wires needed, and then put the flash back together?

With the materials, will not take more than one or two hours.

It took me whole afternoon because I need to search components in my house, actually finally I took them from an old scrap IR TV remote control.

Fourthly, do you even think you absolutely need the entire Sony flash unit to wire up a trigger? Wonder what would happen if you had a little chunk of circuit board with "fingers" disconnected (except for the 2 connection fingers that have the wires soldered to them, plus the resistors and transistor you need), that you plugged into the Sony flash connector slot. Could that little circuit board if it was somehow insertable and removable still function as a flash trigger? Or does the entire flash need to be plugged in, in order to convince the Nex camera that it's time to send out signals to the top port.

Because the size of the Sony slot connector, it is almost impossible to replace by a home made printed circuit board, and for sure will not have the same contact precision than a connector.

And I think this is a proprietary connector, really I didn´t research if exist this option.

What you say is what Shadow hot shoe does, they built this connector replacement.

But I will add something to this issue.
With my mod, you can continue using on camera flash.

Suppose you want to use external flash for side lighting, and on camera flash for main portrait flash with some diffuser, then you need both.

Thanks in advance.

Now I continue my plan, I´m already working in V2!!
I will purchase this cheap Hot Shoe Pixel TF-321

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=261006845627

Then will modify the base (remove it and make the base flat) and fix it at top of Sony Flash cover.
Then I will get a Hot Shoe connection plus PC Sync port and no external cables.

For sure on this shoe I ONLY will use a Wireless Trigger (I´m buying a couple of Yongnuo RF603) since this configuration can´t support the weight of a full flash.

Same as Shadow shoe, I think if you attach a big flash there, the camera connector can suffer some problem.
Sony Flash is cheap to replace, but the camera is not.

Thanks for all your comments, I think this will help and encourage other guys to do this mod.

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
richg101 Regular Member • Posts: 226
Re: fabian does your mod suppress Sony flash output?

fabianbono wrote:

This is the weak point of the mod.
With Sony flash down (off) you will not get the LCD screen brighten up.

This also could affect your AF function, even with AF illumination assistance light.

Issue is to operate the camera on a very dark condition (or no light at all), then I rise up the Sony Flash (to brighten the LCD screen), half press the shutter button to get the AF make focus, then while maintain the half pressed shutter button, down the Sony Flash and then shoot the picture.

could you mod the 'flash up/flash down' switch to always be set to the 'flash up' setting? then disconnect the flash bulb so it runs as if the bulb has blown, with no flash focus assist. will the orange focus light still function when flash is attatched and set to 'flash up'?

fabianbono
fabianbono OP Regular Member • Posts: 190
Re: fabian does your mod suppress Sony flash output?

ure

richg101 wrote:

fabianbono wrote:

This is the weak point of the mod.
With Sony flash down (off) you will not get the LCD screen brighten up.

This also could affect your AF function, even with AF illumination assistance light.

Issue is to operate the camera on a very dark condition (or no light at all), then I rise up the Sony Flash (to brighten the LCD screen), half press the shutter button to get the AF make focus, then while maintain the half pressed shutter button, down the Sony Flash and then shoot the picture.

could you mod the 'flash up/flash down' switch to always be set to the 'flash up' setting? then disconnect the flash bulb so it runs as if the bulb has blown, with no flash focus assist. will the orange focus light still function when flash is attached and set to 'flash up'?

In the picture "Imagen07" you can see the flex board of the flash.

At right you see the two flex going to the connector, and a third one (the bottom one in the photo) that is the mechanical switch that control the on/off of the flash.
The case push this switch when down, then put the flash in off status.

Just need to fix this switch to the desired value, or modify his connection to force the status that you want.

But again, this will reduce the value ranges on speed and aperture in your camera, that may be can affect your exposure desired values.
Flash OFF you have the full range of values to choose.

The AF assist light I think is independent of flash setting. It lites up when the camera detect a low contrast/low light scene, so need the extra help of that light.
I didn't try on the camera, but is how should work.

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
RussellInCincinnati Veteran Member • Posts: 3,201
richg101, hadn't thought of replacing flash switch

richg101: could you mod the 'flash up/flash down' switch to always be set to the 'flash up' setting? then disconnect the flash bulb so it runs as if the bulb has blown, with no flash focus assist.

Ah, yes. Really just replace the flash up/flash down switch with some kind of punch-it tiny toggle switch. Then you could turn the thing on and off without the annoyance of lifting the flash.

Hmm, and then folks like me who will never use the on-camera flash could just glue/lock the little $40 dollar Nex flash down so that it never flops up or around. And we won't have to figure out how to put the little spring hinge back together properly. That particular end result is a "hot shoe adapter" that (in the narrow terms of parts outlay) costs less than the NexProShop adapter. And it does something, viewfinder brightening, that the NexProShop adapter doesn't.

That does it. Am going to modify the little Sony Nex flash, and as you suggest disconnect the flash bulb. Which has to work ok, because a flash bulb in the "off" state doesn't conduct electricity. I.e. the camera firmware can't possibly guess that the flash bulb "isn't there". Want to figure out how to get a hot shoe on top of it, an issue Fabianbono is also pondering below.

Fabianbono: Now I continue my plan, I´m already working in V2!! I will purchase this cheap Hot Shoe Pixel TF-321 http://cgi.ebay.com/ws/eBayISAPI.dllViewItem&item=261006845627 , then will modify the base (remove it and make the base flat) and fix it at top of Sony Flash cover. Then I will get a Hot Shoe connection plus PC Sync port and no external cables.

Yes, let us know how that works out, it is by far the best thing to do. Would you consider letting a few of us mail you a Sony flash unit, and the Hot Shoe, and the switch and resistors and transistor that you tell us to buy, perhaps with a prepaid mailer.? We'd pay you to send back a disabled, non-hinged (i.e. glued into the down position) Sony flash unit that has become a hot shoe adapter. With a tiny switch somewhere on it, to turn the thing on and off without having to raise or lower anything.

Fabianbono: For sure on this shoe I ONLY will use a Wireless Trigger (I´m buying a couple of Yongnuo RF603) since this configuration can´t support the weight of a full flash.

Are you prepared to add the simple 100+K ohm resistor, to make one of the RF603's function as a permanent transmitter? That modification works perfectly . And even if you never labeled it, you can always tell which of your transceivers has been modified to be a transmitter. Just turn on your modified RF603, it'll be the one that has both green lights go on instead of just one.

The Nex is a particularly nice flash camera with a compact wireless remote flash trigger on it. In terms of always-bright viewfinder, focus peaking in low light, the not-superb-wide-open convenient light lenses function fine at modest apertures, etc.

fabianbono
fabianbono OP Regular Member • Posts: 190
Re: richg101, hadn't thought of replacing flash switch

RussellInCincinnati wrote:

That does it. Am going to modify the little Sony Nex flash, and as you suggest disconnect the flash bulb. Which has to work ok, because a flash bulb in the "off" state doesn't conduct electricity. I.e. the camera firmware can't possibly guess that the flash bulb "isn't there". Want to figure out how to get a hot shoe on top of it, an issue Fabianbono is also pondering below.

As my understanding, if you just remove the flash lamp, it will work as you say.

I also guess that the electronics on the flash board can't detect the bulb failure.

In that worst case, just need to replace the lamp for some hi watt resistor to discharge the capacitor and simulate the complete bulb fired.

Fabianbono: Now I continue my plan, I´m already working in V2!! I will purchase this cheap Hot Shoe Pixel TF-321 http://cgi.ebay.com/ws/eBayISAPI.dllViewItem&item=261006845627 , then will modify the base (remove it and make the base flat) and fix it at top of Sony Flash cover. Then I will get a Hot Shoe connection plus PC Sync port and no external cables.

Yes, let us know how that works out, it is by far the best thing to do. Would you consider letting a few of us mail you a Sony flash unit, and the Hot Shoe, and the switch and resistors and transistor that you tell us to buy, perhaps with a prepaid mailer.? We'd pay you to send back a disabled, non-hinged (i.e. glued into the down position) Sony flash unit that has become a hot shoe adapter. With a tiny switch somewhere on it, to turn the thing on and off without having to raise or lower anything.

I can consider to modify your flashes!, just need to check if possible to handle the mailing without problems.
Our customs here a little harder....but no impossible.
Even that I can consider get some F7S units, convert, and put them on ebay!

Fabianbono: For sure on this shoe I ONLY will use a Wireless Trigger (I´m buying a couple of Yongnuo RF603) since this configuration can´t support the weight of a full flash.

Are you prepared to add the simple 100+K ohm resistor, to make one of the RF603's function as a permanent transmitter? That modification works perfectly . And even if you never labeled it, you can always tell which of your transceivers has been modified to be a transmitter. Just turn on your modified RF603, it'll be the one that has both green lights go on instead of just one.

I already analyze the mod on RF603, to add the resistor.
But I was wondering if the J6 place on the board, is some of the shoe pins.

That is why I purchase that hot shoe to make the mod, since it have all the Canon Pins.

Then, instead of modify the RF603, I can force the signal from inside the hot shoe, just need a logical one voltage!.
But until I receive my RF603 unit, I only can continue researching on Internet.
I didn't find pictures of circuits of RF603 inside yet.

And because my current workload, i'm doing this just in the few free time I have.

Let's continue improving our Nex!!!

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
RussellInCincinnati Veteran Member • Posts: 3,201
wait, attach/power RF603 transmitter directly to flash

Fabianbono, a further idea. How about using attaching a $20 dollar Yongnuo RF-603c transmitter directly to the top of the little Sony Nex flash ? And just skip the entire step of the bulky, $10 dollar, "TF-321 Canon E-TTL Flash Hot Shoe to PC Sync Adapter", that simply provides a mechanical hot shoe and pc cord adapter that the RF-603 already has .

  1. The NPShsa NexProShop hot shoe adapter costs $80 dollars, and you don't even get viewfinder-brightening with it, because the the NPShsa doesn't "look like a flash" to the Nex.

  2. There are many folks who would be very happy with modifying a $40 dollar Sony Nex flash to make it into a radio transmitter that doesn't flash at all. That's the main insight here, what's wrong with destroying a $40 flash to make it serve as a hot shoe adapter, if you were willing to pay $80 for a NexProShop adapter anyway?

  3. Yongnuo RF-603 transceivers only cost around $20 dollars.

  4. The RF-603 has an on-off switch that could serve the same function as the Sony flash hinge-on-off switch.

  5. RF-603 can probably run fine off of a tiny bit of 5 volt POWER.

  6. Pin 7 on the 14-pin proprietary Nex flash connector is 5 volt POWER.

  7. RF-603 itself comes with a hot shoe on top, and a pc sync cord output on its side. Plus it of course serves as a cordless radio trigger anyway.

Here's how we'd do it:

  1. Disassemble Sony Nex flash.

  2. Discard flash hinge switch and hinge springs. After all, we're going to permanently glue the flash hinge into some single position. Probably glue the flash hinge so that the flash is always "down".

  3. Discard flash tube, the light output device. This "flash" is going to be just a radio transmitter now, it will never emit any light again.

  4. Replace main, big Nex flash capacitor with a tiny one of same voltage rating . "Big" (percentage wise) weight savings here. Now the modified "flash" will never drain any power to speak of, nor will it take any time to "recycle".

  5. Disassemble RF-603 transmitter.

  6. Cut off the input wires from the bottom hot shoe of the RF603, they are going to be instead soldered directly to the output wires of the modified flash described below.

  7. Throw away the RF-603 batteries, we're going to power it via the 5 volts on the Nex flash pin 7. Wow, now the RF-603 weighs only 38 grams.

  8. Do the RF-603c remote flash trigger modification we both know about, that I described painstakingly here: http://forums.dpreview.com/forums/read.asp?forum=1042&message=40971346 Really all this modification does is run 5 volts through a 100Kohm resistor to J6 in the RF-603. But the 5 volts now can come from pin 7 of the Nex flash unit. The RF-603 transceiver will now function always as a transmitter.

  9. Disconnect the RF-603 leads to the RF-603 on-off switch, and tie them permanently together. We don't need a separate on-off switch for the Yongnuo transmitter, it will come on whenever we power up the modified "flash".

  10. How do we power the RF603 now? Using Nex port pin 7. The routing of pin 7 power will be first to the RF603 on-off switch, which we just disconnected above.

  11. From the output side of the RF603's on-off switch, we route a little bit of power through a 100K resistor to RF603 J6 point.

  12. Another power lead branches off from the RF603 on-off switch, to serve as the main power source for the RF603.

  13. A final power lead goes from the output side of the RF603 on-off switch, to just beyond the now-disconnected hinge switch in the flash, to become the main "flash" power as well.

  14. inside the now-empty battery compartment of the RF603, put all resistors, transistors etc needed to implement your Sony flash mod. But the output wires, the outgoing trigger signal, from that flash modification will connect into the very nearby "bottom hot shoe input wires" of the RF603, that we had cut off from the bottom hot shoe already above.

  15. Glue 40-odd-gram RF603 directly to top of casing of modified Sony flash. Too bad we can't easily remove the bottom hot shoe from the RF-603 (or maybe we can, haven't analyzed this, it's not important in any case. Pun intended.).

Result is a Sony Nex flash, lightened without flash tube or big internal capactor, permanently set into the compact "down position", with a Yongnuo RF603 permanently glued atop it. The RF603 providing a standard PC sync hot shoe atop it, a standard PC sync cord output on its side, and the thing is putting out a radio remote flash trigger as well that will be "automagically" picked up by other $20 dollar unmodified RF603 transceivers. Whole thing neatly powered by the Nex main battery.

Since the RF603's are only $20 dollars, and heck you were going to pay $10 dollars for a little dead hot shoe adapter, this isn't a bad mod even if you don't use the RF603 as a radio remote flash trigger.

fabianbono
fabianbono OP Regular Member • Posts: 190
Re: wait, attach/power RF603 transmitter directly to flash

Dear Russell, how far we are going!!! it's amazing how a brainstorm like this can provide these results.

First of all I like to mention something, that is the base of my project.
My C3 is my family camera, so it is used by me or my wife also.

But she only uses on iAuto mode (that I must set before turn it off!!) and if need some case, use the flash.

Also sometimes I don't want to travel with a full bag of stuff, just the camera on his small bag hung from my shoulder.

Then, I need to have available the original flash too, just in case I use the C3 as Point and Shot.

And last, also I like to use the C3 mounted on a bracket, with the Yongnuo 560II flash at side, just connected by PC cable, without using Wireless triggers.

Basically, I don't want to loose any feature on the camera or in the flash.

Then, some comments based on your very interesting post.

RussellInCincinnati wrote:

Fabianbono, a further idea. How about using attaching a $20 dollar......

It is perfect idea for many people, but as I mention before, not for me. I want it all!!!

  1. The NPShsa NexProShop hot shoe adapter costs $80 dollars, ....

True.

  1. There are many folks who would be very happy with modifying a $40 dollar Sony Nex....

More true.

  1. Yongnuo RF-603 transceivers only cost around $20 dollars.

Yes, I pay US$34 for a couple.

  1. The RF-603 has an on-off switch that could serve the same function as the Sony flash hinge-on-off switch.

  2. RF-603 can probably run fine off of a tiny bit of 5 volt POWER.

I think just use 3V inside from two AAA, is enough for current CMOS technology.
But agree that can be powered on that way.

  1. Pin 7 on the 14-pin proprietary Nex flash connector is 5 volt POWER.

I think yes, I didn't measure it when open mine.

  1. RF-603 itself comes with a hot shoe on top, and a pc sync cord output on its side. Plus it of course serves as a cordless radio trigger anyway.

Here's how we'd do it:

......

  1. Discard flash tube, the light output device. This "flash" is going to be just a radio transmitter now, it will never emit any light again.

Here I suggest to add some resistor to simulate the bulb, and discharge the capacitor to complete the circuit functioning.
We don't know the chip inside flash what kind of controls make on the circuit.

  1. Replace main, big Nex flash capacitor with a tiny one of same voltage rating . "Big" (percentage wise) weight savings here. Now the modified "flash" will never drain any power to speak of, nor will it take any time to "recycle".

Agree.

......

  1. A final power lead goes from the output side of the RF603 on-off switch, to just beyond the now-disconnected hinge switch in the flash, to become the main "flash" power as well.

We need to investigate, but need to care on how much current use the RF603, in order to save the camera battery, that will serve all the stuff!!

May be because we remove the flash (bulb+capacitor), that battery saving is the same to power the RF603.
But better to confirm.

  1. inside the now-empty battery compartment of the RF603, put all resistors, transistors etc ......

  2. Glue 40-odd-gram RF603 directly to top of casing of modified Sony flash. Too bad we can't easily remove the bottom hot shoe from the RF-603 (or maybe we can, haven't analyzed this, it's not important in any case. Pun intended.).

Warning!!, be careful where you glue the RF603, since you need to continue accessing the RF-603 battery compartment to modify the small DIP Switch to change the Channels!!!
If not will be a mess to do it.

Result is a Sony Nex flash, lightened without flash tube or big internal capactor, permanently set into the compact "down position", with a Yongnuo RF603 permanently glued atop it. The RF603 providing a standard PC sync hot shoe atop it, a standard PC sync cord output on its side, and the thing is putting out a radio remote flash trigger as well that will be "automagically" picked up by other $20 dollar unmodified RF603 transceivers. Whole thing neatly powered by the Nex main battery.

Again, here I don't totally agree on the idea to set permanent the Flash On mode to brighten the LCD screen, since you also ALWAYS will block some ranges on Aperture and Shutter speed on your camera. (Hell yes, the Sony firmware do that...)
This give you less control on the exposure in my point of view.

Since the RF603's are only $20 dollars, and heck you were going to pay $10 dollars for a little dead hot shoe adapter, this isn't a bad mod even if you don't use the RF603 as a radio remote flash trigger.

Totally agree with your idea.
Cheap solution, and with more functions that other ones.
Just need a little of DIY practice, a magnifying glass and a soldering iron.

I will continue working on this when I receive my purchased items, this is around 3 weeks.
In the meantime, just continue researching!!

See you!

 fabianbono's gear list:fabianbono's gear list
Sony Alpha NEX-C3 Nikon D5200 Nikon AF-S DX Nikkor 18-105mm f/3.5-5.6G ED VR Nikon AF-S DX Nikkor 35mm F1.8G Sony E 18-55mm F3.5-5.6 OSS +8 more
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