Regarding Camera Wireless Flash Trigger

Hi All.

I want to make a Wireless based DSLR Camera Flash Trigger system. Some ques please:

-1. I want to trigger the flash using existing Wireless receiver in the market. For this Wireless communication is there any standard or protocol which all Of-Camera Wireless (RF) Flash receiver manufacturer maintains? So I can develop only the transmitter and use the same protocol to send Wireless commands to trigger flash?

-2. In case I need to design both transmitter and receiver then I need to use Hot-Shoe signal. Can anyone advice detail document how Hot-Show pin and its signal works? I did googled already but did not find much design in terms of helpful for electronics design.

-3. Is there any standard connector PCB Mount for Canon/Nikon/Sony Hot-Shoe male and female?

Thanks in advance.

Regards.

Ok, just tripped over this thread and I realize it’s getting a bit old. The lack of responses indicate that this is a pretty thin area in general photography. but I’ve some experience playing here. So see my thoughts below...

sakibnaz wrote:

Hi All.

I want to make a Wireless based DSLR Camera Flash Trigger system. Some ques please:

-1. I want to trigger the flash using existing Wireless receiver in the market. For this Wireless communication is there any standard or protocol which all Of-Camera Wireless (RF) Flash receiver manufacturer maintains?

Basically, as far as I can fathom, no there isn’t. The protocols are mfr proprietary and not published.

So I can develop only the transmitter and use the same protocol to send Wireless commands to trigger flash?

Not with any realistic practicality unless you have some very specific tools to intercept and analyze wireless protocols on these open frequencies. Not exactly found in a regular diy toolbox.

-2. In case I need to design both transmitter and receiver then I need to use Hot-Shoe signal. Can anyone advice detail document how Hot-Show pin and its signal works? I did googled already but did not find much design in terms of helpful for electronics design.

There is actually quite a bit of info on the various standard hotshot signals. Manual flash is basically just shorting the big central contact and the hot shoe bracket. You can try it with a flashgun. TTL flash is more complex and not nessarily about simple voltages either. It’s also strictly mfr specific too. Best to ignore TTL control...

-3. Is there any standard connector PCB Mount for Canon/Nikon/Sony Hot-Shoe male and female?

Not that I know of.

Thanks in advance.

Regards.

That all being depressingly said, it it not that hard to find wireless units that you can simply interface to using a wired shutter release (see Camtraptions.com) or hack / mashup a cheap unit like the Yongnuo Rf-603. I did the latter. Here are some tips on what I did:

http://camtrapper.com/viewtopic.php?f=113&t=11778 - you may have to register to view the pics!

Thanks Richard B99 and sirhawkeye64.

I checked the Camtrapper and its one of the features I like to implement i.e. Motion Sensor based Trigger.

I know there are available low cost Wireless Trigger available but my project have some specific needs where I want to implement Flash Control (both Manual and TTL).

However, past days I have more study on TTL and now my understanding is much concrete. Like to introduce some more qus please:

-1. So far I found TTL is SPI communication so I think by reverse engineering its possible to decode the SPI data. But in case of Canon E-TTL and Nikon I-TTL if I am able to decode the control signals then is it permitted to implement in commercial product like Yongnuo or PocketWizard doing?

-2. My aim is to make both Transmitter (Tx) and Receiver (Rx) device where Tx will consist of some Sensors to trigger DSLR shutter in different conditions. In my Tx device I am already implementing Bluetooth 4.0 (BLE) for some other features but will it be good to use BLE for the Flash Communication i.e. adding BLE in Rx as well? Not sure if its the best RF. As for Flash I need to trigger it very fast when Camera Shutter is clicked so delay (wireless transmission latency) needs to be min as possible.

Thanks again.

Regards.

sakibnaz wrote:

Thanks Richard B99 and sirhawkeye64.

I checked the Camtrapper and its one of the features I like to implement i.e. Motion Sensor based Trigger.

I know there are available low cost Wireless Trigger available but my project have some specific needs where I want to implement Flash Control (both Manual and TTL).

However, past days I have more study on TTL and now my understanding is much concrete. Like to introduce some more qus please:

-1. So far I found TTL is SPI communication so I think by reverse engineering its possible to decode the SPI data. But in case of Canon E-TTL and Nikon I-TTL if I am able to decode the control signals then is it permitted to implement in commercial product like Yongnuo or PocketWizard doing?

Interesting you found TTL uses SPI.  I’ve no doubt it is a serial protocol but have no means of analyzing it and have not found a definition of it anywhere.  If you have access to a suitable protocol analyzer you may have more luck.

To the question, I don’t know if it permitted but I suspect reverse engineering the interface isn’t illegal under patent/copyright protections.  I don’t believe Canon or Nikon will license or share their protocols.  But the independent lens manufacturers and electronic mfrs have been reverse engineering for years so, draw your own conclusions from that.

-2. My aim is to make both Transmitter (Tx) and Receiver (Rx) device where Tx will consist of some Sensors to trigger DSLR shutter in different conditions. In my Tx device I am already implementing Bluetooth 4.0 (BLE) for some other features but will it be good to use BLE for the Flash Communication i.e. adding BLE in Rx as well? Not sure if its the best RF. As for Flash I need to trigger it very fast when Camera Shutter is clicked so delay (wireless transmission latency) needs to be min as possible.

Sorry, you are beyond where my electronics and data networking experience finishes!  But I can say that the range of these 2.4GHz transmitters is pretty good (around 100m) and so Is roughly around the same as BLE.  Not sure how BLE protocols work in terms of establishing and maintaining handshake connections.  As a user, it always seems pretty slow - I suspect it’s quite a chatty protocol.  The rf devices seem very quick but I don’t think they maintain a networked connection at all.  If the receiver hears a fire signal on its frequency it does.  Transmitter doesn’t care or know if anyone is listening.  That’s simple and fast as there are no network overheads in the manual mode triggers; plus, these simple devices aren’t mucking about trying to do several things at once and waiting for stuff on queues.

Thanks again.

Regards.

Thanks Richard B99 for reply.

Yes, you was right its TTL signals are Serial Peripheral Interface bus (SPI). I found some detail here.

https://billgrundmann.wordpress.com/2009/03/18/sniffing-canons-ettl-protocol-2/

Yes, BLE may be slow. Surely the others not using Bluetooth. Research about it what will be the best RD for my case.

Anyways, high chance the TTL SPI decide will be very tough things. So at least I'll implement then manual Wireless Flash Trigger. But it will be best if there is any other way to control the Flash Settings (rather TTL). So I can implement remote settings change from Tx end but trigger will be manual in Rx.

Is there any standard interface for Flash to control settings ... like Power, Zoom etc? I think no though ...

Regards.

sakibnaz wrote:

Thanks Richard B99 for reply.

You’re welcome.

Yes, you was right its TTL signals are Serial Peripheral Interface bus (SPI). I found some detail here.

https://billgrundmann.wordpress.com/2009/03/18/sniffing-canons-ettl-protocol-2/

Yes, BLE may be slow. Surely the others not using Bluetooth. Research about it what will be the best RD for my case.

Anyways, high chance the TTL SPI decide will be very tough things. So at least I'll implement then manual Wireless Flash Trigger. But it will be best if there is any other way to control the Flash Settings (rather TTL). So I can implement remote settings change from Tx end but trigger will be manual in Rx.

I had a couple of further thoughts here about TTL vs manual flash based on my experience that you may find useful:

- you mentioned you need fast flash triggering.  It’s worth mentioning that TTL tiggers, in the scheme of things a good deal slower than manual.  This is because or the pre-flash mini  burst of flashes.  If you want fast with minimum lag on your original trigger signal manual is much better.  Almost the only way to go.  For fastest, it’s probably wired connections but I’ve not noticed any material difference here though have with TTL but I shoot wildlife and not bullets!

- I don’t know your application but I find TTL less useful for off camera multi flash setups.  Modeling with 2 or 3 flashguns (where I typically am) seems to be as easy to do by manual adjustment and you quickly get the hang of what you want to see.  I find I can normally look at the set up, judge flashgun distances, power settings and get it right within a few test shots.  At that point I want the setup to stay the same and not tweak itself with each shot.

- The TTL preflashes can and do affect some of my animal subjects.  The burst is long enough for them to react sometimes.  A single short low power manual flash seems not to bother them.

So in consequence, manual is my preference rather than only option. (I could have easily modified TTL units and cost is not an absolute consideration for me.)  That’s not to say I don’t find TTL useful.  On camera for balanced fill flash I find it very useful.  Thus, you may wish to consider whether going down the TTL route is really necessary for your project.

Is there any standard interface for Flash to control settings ... like Power, Zoom etc? I think no though ...

Er, no.  All proprietary by manufacturer and sometimes changes over time within a mfrs own range.

Regards.

good luck with your project.

Thanks Richard B99 for detail reply.

Actually I know TTL is not used mostly where Manual is the need for pro. But in point f commercial product development it needed TTL as feature enhancement. That's why only considering TLL in development else manual is the path to go

Two more ques I like to ask:

- So far my research was only on Speedlights. But now also checking Strobes. In most case how professional photographed trigger a strobe? I mean by wire or wireless? Is it all PC Sync port based? Actually I am thinking on my Receiver (Rx) end with Hot-Shoe if I add a PC Port then will it enough to control all Strobes? Is it possible to do TTL with Strobes? May be my ques is dumb.

- For all High Speed Photography  sensor ... Sound, Light, PIR Motion widely used I found. Is there any other Sensor which can add more values? (Though this ques not related with this thread).

Thanks in advance.

Regards.

sakibnaz wrote:

Thanks Richard B99 for detail reply.

Actually I know TTL is not used mostly where Manual is the need for pro. But in point f commercial product development it needed TTL as feature enhancement. That's why only considering TLL in development else manual is the path to go

Two more ques I like to ask:

- So far my research was only on Speedlights. But now also checking Strobes. In most case how professional photographed trigger a strobe? I mean by wire or wireless? Is it all PC Sync port based? Actually I am thinking on my Receiver (Rx) end with Hot-Shoe if I add a PC Port then will it enough to control all Strobes? Is it possible to do TTL with Strobes? May be my ques is dumb.

I don’t use studio strobes so this is all I have gleaned in passing.  My understanding was that strobes tended to use the old pc sync.  I don’t know if they have added proprietary sockets more lately.  Probably worth asking this question on the studio lighting forum.

- For all High Speed Photography sensor ... Sound, Light, PIR Motion widely used I found. Is there any other Sensor which can add more values? (Though this ques not related with this thread).

The obvious one is beam break triggers with IR or laser source. And the exotic Lidar types.

Thanks in advance.

Regards.

Thanks Richard B99.

Yes agree, strobes uses still PC Sync. But some strobe have TTL but internally handle by their wireless.

About Sensor, yes I also think about Laser as if the Light Sensor is there so it can detect Laser beam as well. LiDAR will be nice but costly. Where this Sensor can be apply? In Wildlife Camera Trap? Or other possibility can be? For Motion sense now I have in my list PIR, Thermal and LiDAR. If I pick only 1 of this then which will be best you think?

Regards.

Hi. Yes it will be good but ultrasonic is big in size to get good range like 15 - 20 Feet ... ?

Can you show what device you used before with ultrasonic sensor .... any web link?

By the way, I am also thinking of Thermal Sensor mainly featuring Wildlife Camera Trap. Ant comments on Thermal?

Thanks.