How do remote shutter releases work? Calling electronics bods

[Roger Ramjet]

Hi all, I'm looking at a wireless remote shutter release from eBay - item no 370156312827 although there are umpteen which all look the same. My question is how do these units trigger the camera? Is there a voltage pulse which gets applied at the flash shoe, or does it just short out a couple of pins on the camera?

I'm asking because apart from using it to control shutter release on my Canon 450d I might want to also use it to switch a relay to remotely control the auto throttle on a small petrol generator.

I'm sure someone out there knows how these things interface to a camera. :shrug: TIA

 

[colonel_mustard]

I think they probably short out some pins. You can probably test one easily enough with a multimeter.

 

[Blue Eagle]

A wireless one would be infra-red surely, which may are may not be very complicated to emulate.

For your purpose you could just detect a change in potential at the switch and have a separate circuit controlling the relay, which would avoid it interfering with the function of the first.
I dont think it would be too difficult to do, but would probably be quite bulky and fragile unless you fit the whole thing into a pre-bought housing like an ABS box.

 

[Roger Ramjet]

I think they probably short out some pins. You can probably test one easily enough with a multimeter.

Thanks yes I can test one but I haven't bought it yet, just considering the viability. Might as well just get it though as I'll use it on the camera if nothing else.

 

[Roger Ramjet]

A wireless one would be infra-red surely, which may are may not be very complicated to emulate.

The ones I'm looking at are RF (433MHz) with 100m range.

For your purpose you could just detect a change in potential at the switch and have a separate circuit controlling the relay, which would avoid it interfering with the function of the first.
I dont think it would be too difficult to do, but would probably be quite bulky and fragile unless you fit the whole thing into a pre-bought housing like an ABS box.

I'll also need to figure out how to convert what is a momentary action from the shutter release into a latching two state output. ie. one button press = on, next button press = off.

Will have to get my flip flops out!

 

[Sparkles33]

Ah I bought a wired one, didn't think to get a remote one...what a div...

 

[Blue Eagle]

What exactly do you want the whole system to do? Essentially post your inputs and outputs and then we'll figure out the bit in between.

 

[Canon Bob]

The shutter release is a simple 3 wire system.....one common and two contacts for focus and shutter.

Bob

 

[Roger Ramjet]

What exactly do you want the whole system to do? Essentially post your inputs and outputs and then we'll figure out the bit in between.

Well the output will need to duplicate the function of a single pole double throw switch, not sure whether it has 12V across the contacts or 240V (need to investigate the generator further) but I'm thinking if I can switch a relay using the shutter release receiver I'm covered for all eventualities.

Canon Bob has confirmed the input will be the two poles from the shutter release receiver (focus and shutter), which I assume are open collector type good for at least 100mA or so of current.

I'm now leaning towards this unit instead of the eBay ones:

http://www.dealextreme.com/details.dx/sku.13175

Mainly because there's enough info there for me to be confident I can make it work ahead of buying it.

The way forward is probably for me to get one of these units and have a play then come back with any further questions if it all gets a bit too much for my little 'ed to cope with. :bonk:

 

[Blue Eagle]

Erm....what about
Input: PTM button on trigger is pressed momentarily
Output: camera triggers and .... happens

I dont get what the generator is for and the problem is see is the trigger doesnt know the exposure, unless it is used in bulb mode. (and it's not like you will rev up the motor for 1/320s anyway)
So thinking on a macro scale, when A happens, what does B do?

 

[Chaz Photos]

Hi all, I'm looking at a wireless remote shutter release from eBay - item no 370156312827 although there are umpteen which all look the same. My question is how do these units trigger the camera? Is there a voltage pulse which gets applied at the flash shoe, or does it just short out a couple of pins on the camera?

I'm asking because apart from using it to control shutter release on my Canon 450d I might want to also use it to switch a relay to remotely control the auto throttle on a small petrol generator.

I'm sure someone out there knows how these things interface to a camera. :shrug: TIA

why not make on out of a wireless door bell depending on what it is you need to switch there are different ways you can do this BUT remember it is only a switch and not a variable such as working a servo

 

[Roger Ramjet]

Erm....what about
Input: PTM button on trigger is pressed momentarily
Output: camera triggers and .... happens

I dont get what the generator is for and the problem is see is the trigger doesnt know the exposure, unless it is used in bulb mode. (and it's not like you will rev up the motor for 1/320s anyway)
So thinking on a macro scale, when A happens, what does B do?

Sorry if I'm being confusing. I didn't want to go into huge detail to save from boring people with all the details of why I'm doing this, but if you can bear with me I'll explain.

I'm not trying to trigger a camera and generator at the same time, I'm primarily going to use the shutter release to control my camera but then on some days I'll use it to remotely control the generator instead. The generator will be used to charge some big batteries to fly this thing:

The generator has an auto throttle feature which winds down the throttle to minimum to save fuel and reduce noise but if you start a charger while it's at minimum throttle it will stall the engine. But once charging is in progress it's safe to put on minimum throttle. So the procedure is to switch off auto throttle, start charger then re-engage auto throttle. Easy enough but the generator lives at the end of a 25m extension lead and I'm getting a bit bored walking too and fro. Hence the requirement for the wireless remote to switch some relays to interface to the switch on the generator. And on other days to take pictures with my camera!