DIY LED trigger flash

[oskar 6]

Using my DX-1G Sea&sea camera extensively last week in cold water, i noticed that (part from slow processing of RAW) I had to wait for the camera's flash to recycle while the YS110 recycled lightning fast.

 

Has anyone tried a small LED slave trigger in the hot shoe of the camera instead of the built in flash?

 

It would not require the camera to recycle the flash, and would not use camera's battery. If properly aligned, a very low power flash would be needed.

 

 

Comments? Anyone tried this? Anyone that knows the specification of the hotshoe connector?

 

 

Cheers

/O

[diver dave1 23]

I made the same suggestion to Ikelite so their DSLR housings could use fiber optic connections. I got not no response.

[CheungyDiver 53]

Using my DX-1G Sea&sea camera extensively last week in cold water, i noticed that (part from slow processing of RAW) I had to wait for the camera's flash to recycle while the YS110 recycled lightning fast.

 

Has anyone tried a small LED slave trigger in the hot shoe of the camera instead of the built in flash?

 

It would not require the camera to recycle the flash, and would not use camera's battery. If properly aligned, a very low power flash would be needed.

 

 

Comments? Anyone tried this? Anyone that knows the specification of the hotshoe connector?

 

 

Cheers

/O

 

 

 

Yes I have tried several. Some I have made myself. Zillion Housings uses a infrared flash trigger circuit inside their housings. Only trigger no TTL. Depending on which camera ie. Nikon or Canon TTL is complex. LED flash used in mobile phones uses a high capacity micro capacitor and is small enough to be fitted inside some housings. Some more experiment is needed. One has to be careful not to mix up the trigger pin to the signal pins otherwise one could fry the camera circuit. I have not had a satisfactory circuit that could do what I want - TTL. Pop up flash or built-in flash iwith fibre optic cable to optical slave strobe is still the most reliable for the time being.

 

Cheers

 

David

[oskar 6]

LED flash used in mobile phones uses a high capacity micro capacitor and is small enough to be fitted inside some housings. Some more experiment is needed. One has to be careful not to mix up the trigger pin to the signal pins otherwise one could fry the camera circuit. I have not had a satisfactory circuit that could do what I want - TTL.

 

 

Do you have a pin layout of the hotshoe? I tought the trigger pin's would be standardized , while the TTL sense may be different per make, correct? I'm happy with trigger so far, and make do with manual flash setting.

[aponsin 0]

Do you have a pin layout of the hotshoe? I tought the trigger pin's would be standardized , while the TTL sense may be different per make, correct? I'm happy with trigger so far, and make do with manual flash setting.

 

I just stumbled upon that post, and this describes exactly what I wish I could do... Any progress regarding this, I am terribly interested !

 

I have a dx-2g housing, but due to a pb my pop-up flash is broken, therefore I can no longer use the optical cable to trigger my external strobe (ys-17), so I was thinking about finding a way to mount a miniature flash on the hot show, or build some sort of LED flash to trigger the strobe...

 

Any ideas ?

 

Alex

[oskar 6]

Sorry, no not on my end. David?

[ChrigelKarrer 52]

Such a LED trigger or better a micro strobe tube would realize the possibiliy to use optical triggered slave strobes on Ikelite DSLR housings. And exactly that may be the reason that Ikelite did not responded to diver daves1 suggestion to Ikelite.

 

Chris

[CheungyDiver 53]

Sorry, no not on my end. David?

 

 

Hello

 

I am still working on a eTTL or ITTL optical trigger. No luck yet. Nikon iTTL is more hopeful. The Zillion manual optical circuit is the only way at the moment. Not a good idea to trigger a flash tube inside a housing. LED flash is the way to go.

 

For hotshoe pin idagram just Google it. Here is a link to Nikon pin diagarm. Switch to Google images.

 

http://www.google.com/images?hl=en&q=n...sa=N&tab=wi

 

Cheers

 

David

[Nextwo 1]

Hello

 

I am still working on a eTTL or ITTL optical trigger. No luck yet. Nikon iTTL is more hopeful. The Zillion manual optical circuit is the only way at the moment. Not a good idea to trigger a flash tube inside a housing. LED flash is the way to go.

 

For hotshoe pin idagram just Google it. Here is a link to Nikon pin diagarm. Switch to Google images.

 

http://www.google.com/images?hl=en&q=n...sa=N&tab=wi

 

Cheers

 

David

 

So why is nobody/companies do this? TTL I mean. You get quicker recycle time and save battery on your camera, no need for TTL converter.

 

 

Dag

[CheungyDiver 53]

So why is nobody/companies do this? TTL I mean. You get quicker recycle time and save battery on your camera, no need for TTL converter.

 

 

Dag

 

 

Part of the problem is to do with the speed of the digital cameras coming out in the consumer market. Strobes with optical slave function has to play catch up. Inon is now sTTL type 4 which is the forth generation strobe. Works with most of the Canon, nikon and other brand of digicams. Believe me I am not the only one trying to hack it. Optical TTL I mean. One way around is to

get a small/cheap land flash, house it and trigger the optical slave strobes that way.

 

Cheers

 

David

[fotoscubo714 0]

.....One way around is to get a small/cheap land flash, house it and trigger the optical slave strobes that way.

 

Cheers

 

David

 

Hi David,

 

Can you clarify for me the above statement? I have Canon and will try to understand by this brand.

 

Are you saying that if I take a Canon strobe in a seperate housing it will have TTL capability via fiber optic connection? Or, are you saying to have a small cheap strobe inside on the camera and have this set up trigger underwater strobes (as Inons) via f.o. cable to get TTL?

 

I have been trying to figure out how to have TTL and multiple strobe ratio control from my 7D underwater via fiber optic. I have no clue what process is involved (strobe light or IR signal, or both?), but I use it topside and it works nicely in studio.

 

Any insight be much appreciated

 

 

Bo

[oskar 6]

I suppose the LED flash have evolved a bit since these:

 

http://www.khalus.com.ua/kh/data/component...luxeon/DS49.pdf

 

My hunch is that a LED flash has a slower response time and longer burn time than a discharge tube. Is that so, how does the timings compare?

 

In the data-sheet above seems to suggest that the shortest flash pulse is 50ms

 

 

If it is so that the timings are fundamentally different, it may be hard to mimic the timing and thus preserve the "TTL" functionality.

 

 

Comments please!

 

 

/O

[CheungyDiver 53]

Hi David,

 

Can you clarify for me the above statement? I have Canon and will try to understand by this brand.

 

Are you saying that if I take a Canon strobe in a seperate housing it will have TTL capability via fiber optic connection? Or, are you saying to have a small cheap strobe inside on the camera and have this set up trigger underwater strobes (as Inons) via f.o. cable to get TTL?

 

I have been trying to figure out how to have TTL and multiple strobe ratio control from my 7D underwater via fiber optic. I have no clue what process is involved (strobe light or IR signal, or both?), but I use it topside and it works nicely in studio.

 

Any insight be much appreciated

 

 

Bo

 

 

Hi Bo

 

Just let me clarify about the strobes first. Inon uses sTTL that is their jargon for System TTL and is proprietary system that mimics the flash of many brands of digicam. Canon's eTTL is very difficult to decode by electronic - ie. wire connection. I have only achieved using a manual non-ttl LED circuit inside a housing to manually trigger optical slave strobe. Non-ttl though.

 

 

Housing for Canon speedlites such as the EX 580 is available by various UW casing makers such as Subal and Seacam. These are expensive.

 

Some third party land flashes such as the Sunpak that uses Canon flash protocol (or similar)could work. Often the recycle time is slow but to trigger multiple strobes it has quite an interesting prospect. Unfortunately an external housing for the speedlite will have to use 6 pin cable like the S6. It is kind of defeats the purpose. I often uses a EX 380 speedlite in a custom housing on top of my Canon 5 D mark II for highspeed sync and as mutli-optical slave strobe trigger.

 

I have not tried putting one inside a housing. The most likely one to work is the EX 220 and it does not take up much room but there are no housing in the market that fits both camera and speedlite in the same case. It will have to be custom or DIY modified. I might make one and try for fun.

 

Come to think of it your 7D has a pop-up flash. Why not just use that to trigger all the strobes using fibre optic cables? Does you housing have one or more optical sync bulkhead?

 

regards

 

David

[CheungyDiver 53]

I suppose the LED flash have evolved a bit since these:

 

http://www.khalus.com.ua/kh/data/component...luxeon/DS49.pdf

 

My hunch is that a LED flash has a slower response time and longer burn time than a discharge tube. Is that so, how does the timings compare?

 

In the data-sheet above seems to suggest that the shortest flash pulse is 50ms

 

 

If it is so that the timings are fundamentally different, it may be hard to mimic the timing and thus preserve the "TTL" functionality.

 

 

Comments please!

 

 

Here is my two cents worth. The LED flash in mobile phones are slower and has not much power. At least with the ones I have been tinkering. The capacity for storing the pump charge is rather limited. It is almost a LED light. It is rather limited. The sensitivity of the phone's camera is boost up rather than the flash is providing most of the light.

 

In proper digicams, TTL means Through The Lens. The metering of the ambient light and adjusting the amount of flash to throw out is done through the camera's electronics and the discharge tube is powered by a powerful capacitor pump circuit. UW strobes have even bigger capacitors. An array of flash LEDs powered by lots of capacitors may work. Now all we need to do is work out how iTTL and eTTL really works.

 

 

 

Cheers

 

David

 

/O

[fotoscubo714 0]

Hi Bo

 

........Come to think of it your 7D has a pop-up flash. Why not just use that to trigger all the strobes using fibre optic cables? Does you housing have one or more optical sync bulkhead?

 

regards

 

David

 

Hi David,

 

Thanks for the explanation. I have not yet housed my 7D (but leaning to the Nauticam that has optical). Reports (like those from Backscatter) note slow recycle times when going optical.

 

But what I'm most interested in is using the 7D multiple-flash controller to use the "in-camera" flash-ratio control for macro, so the strobes will need to have the right canon TTL.

 

I need to know where the IR transmitter on the 7D is and where the sensor is on the Canon flash to connect them with an optical cable, and then DIY housing for the flash?

 

Bo

 

P.S. I agree with your signature.

[ChrigelKarrer 52]

More "economic" Housings for the Canon EX580 are available from: Fantasea, 10Bar, Aquatech, Patima.

The LED trigger would be perfect, but it seems to be too complicated to realize.

I would like to use a EX580 on my Patima G11 housing to see if it works better than any other system,

but as i have no EX580 the expenses for Strobe and Housing are quite "prohibitive".

 

 

Chris

Edited June 23, 2010 by ChrigelKarrer

[fotoscubo714 0]

More "economic" Housings for the Canon EX580 are available from: Fantasea, 10Bar, Aquatech, Patima.

The LED trigger would be perfect, but it seems to be too complicated to realize.

I would like to use a EX580 on my Patima G11 housing to see if it works better than any other system,

but as i have no EX580 the expenses for Strobe and Housing are quite "prohibitive".

 

 

Chris

 

Hi Chris,

 

In studio (topside) I'm using an old Canon 550EX, 420EX and a Sigma 500 Super (all 3 compatible as E-TTL slaves to my 7D controller). So, I'm forced to look at a DIY housing project for these. I just need to know where the IR and light flash impulses are generated and received for the proper placement of the thin optical fiber. I may have to look into multiple optical fiber connections to transmit the seperate light and IR, but I shouldn't have to since they are on different frequencies of the visual spectrum. Obviously, I know where the visible light is generated on the 7D flash and the general receiving area on the strobe, but would the beam of a narrow optical cable be enough to transmit all the necessary information?

 

It be really sweet if I could find a way. Perhaps I should just get a Nauticam optical cable first and try some dry experiments to see if anything (I want) works.

 

Bo

[oskar 6]

Quotes did not seem to work there so I cited below.

 

 

My point is (as when we started the thread) we would like too make compact flash with low power usage but very fast recyle time that sits in the hot shoe. The flash is too weak to illuminate any photo. It's sole purpose should be to trigger an external flash via optical fibre.

It would be nice to do this in LED technology, however my concern is whether it can be made as fast as a discharge tube. If we are going to trigger an external flash, say Inon with sTTL, the flash pulses from our flash must have accurate timings according to the camera's control so that the external strobe can mimic/ignore pre-flashes and shut down with the same timing as the internal flash.

 

Cheers

 

 

"Here is my two cents worth. The LED flash in mobile phones are slower and has not much power. At least with the ones I have been tinkering. The capacity for storing the pump charge is rather limited. It is almost a LED light. It is rather limited. The sensitivity of the phone's camera is boost up rather than the flash is providing most of the light.

 

In proper digicams, TTL means Through The Lens. The metering of the ambient light and adjusting the amount of flash to throw out is done through the camera's electronics and the discharge tube is powered by a powerful capacitor pump circuit. UW strobes have even bigger capacitors. An array of flash LEDs powered by lots of capacitors may work. Now all we need to do is work out how iTTL and eTTL really works."

[ChrigelKarrer 52]

Oskar,

sorry we got a bit off-topic.

Your idea of using a micros strobe is a nice one and would help some people (using Ikelite DSLR housings for example) to use optical slave strobes and may be useful for slow recycling times as well. Unfortunately we are talking of 1/60 or more of a second, so the LED must be very quick to light-up, otherwise thew would be always to late to trigger the strobe in the right moment. Once found a solution for that the comes another problem - or better limitation- as optical triggered strobes are sensing the (various) preflashe(s) to archieve a automatic exposure and this works perfectly but it's only possible with a strobe because of it's fast flash rate. Using the LED's may enable triggering tha strobe, but you would have to control exposure manually.

Here a article how S-TTL works: http://www.inon.jp/technical/sttl-auto.html or http://wetpixel.com/i.php/full/inon-d-2000...al-explanation/

 

 

Using the Luxeon Flash-LED the problem with the slow LED may be gone and it should work using it like a generic strobe to strigger the strobe, but there will be no i-ttl/e-ttl from the camera and you have to drive the external strobe in manual mode. Loosing the e-ttl/i-ttl mode may lead that the camera itself will have serious troubles in exposure control and has to be used in manual mode as well.

 

 

 

 

Chris

[bvanant 190]

Yes it is true that the 7D has a built in flash and that is often the best way to use it, BUT the original poster was looking for a way to fire the flash manually not using the strobe at full power. If you use the built in strobe, even at 1/128 power it still will send out pulses to focus that will shoot off your external strobes. A small LED that fired even for 50 ms would allow you to get manual FO control of your strobes without waiting for the internal strobe to recycle or for the internal strobe to trigger the external strobes to send out a focus pulse

Bill

[slowhands 0]

Yes it is true that the 7D has a built in flash and that is often the best way to use it, BUT the original poster was looking for a way to fire the flash manually not using the strobe at full power. If you use the built in strobe, even at 1/128 power it still will send out pulses to focus that will shoot off your external strobes. A small LED that fired even for 50 ms would allow you to get manual FO control of your strobes without waiting for the internal strobe to recycle or for the internal strobe to trigger the external strobes to send out a focus pulse

Bill

 

It is possible to do this. If you just want a manual trigger and will use your strobe in manual, that's very simple. If you want to try to do DSTTL, it is more expensive. How much would people be willing to pay for such a device?

[elanarchist 0]

I'm looking for this too. I have a G10 with a fried internal flash controller but the hot shoe still works. All I want to do is to trigger my strobe in manual and it doesn't have to be pretty. I've searched but all that I've found are the 10bar hot shoe plug http://10kphoto.com/index.php?main_page=pr...products_id=386 or http://scubasymphony.com/shop/index.php?ma...products_id=727 but those are just the hot shoe plug.. Please advise.. Thanks

[zee 0]

I've been looking at making a trigger for my Inons, and came upon this thread... I don't care about TTL, as all my strobe and shooting settings are manual - I just want a trigger, and I don't want the camera flash used to trigger it, simply because I want max battery time, and with the flash down, it may be possible to sync to faster than 1/250...

 

Anyway, I was thinking about building up a circuit, and came upon this...

 

For $35, it may just work (with a little minor tweaking). I'm looking at getting it to fit in a Nauticam housing, though I only just got my 7D, and the housing will be a little while away yet... I'm trying to find dimensions, but by the looks of it, it may just fit in the area that the pop up flash uses - though a little modding may be needed, an dI still need to test if the IR will actually trigger my Inons or not...

 

Z...

Edited April 30, 2011 by zee

[oskar 6]

I finally got around making a prototype hot shoe optical trigger that fits my Sea & sea DX-G1 housing.

 

* A single 1ms flash pulse is provided by the camera in all modes - this means no eTTL. Only a single flash, no pre flashes. This is fine for me as I set the YS110 in "Manual2" and adjust power on the flash directly.

* On land, I got a hit rate of 10/10

 

I'll get back with more details as soon as I have verified results in water too.

 

The DX-G1 is painfully slow when handling raw-files, so I don't seem to shorten the time between shots. But the camera battery should last much longer, and I don't need to ducttape the housing to prevent back-scatter from the internal flash. It will be interesting to see if the hit rate of the YS110 gets better.

 

Cheers

/O

[Benthichi 0]

I'm very interested in this idea...I'm waiting for the 5D MKIII to arrive, and don't want to switch to electrical connections. Looking forward to the update!

 

I finally got around making a prototype hot shoe optical trigger that fits my Sea & sea DX-G1 housing.

 

* A single 1ms flash pulse is provided by the camera in all modes - this means no eTTL. Only a single flash, no pre flashes. This is fine for me as I set the YS110 in "Manual2" and adjust power on the flash directly.

* On land, I got a hit rate of 10/10

 

I'll get back with more details as soon as I have verified results in water too.

 

The DX-G1 is painfully slow when handling raw-files, so I don't seem to shorten the time between shots. But the camera battery should last much longer, and I don't need to ducttape the housing to prevent back-scatter from the internal flash. It will be interesting to see if the hit rate of the YS110 gets better.

 

Cheers

/O

Edited May 29, 2011 by Benthichi