williB

4.6 V at which side ?. ( the cheapo detecter or the canon flash..?? )
Without a schematic of both units , i can only guess as what to do next..

williB

when you touch both terminals of the canon flash unit it goes off ..correct..?
you could use a FET to make this connection..but you would need to know what happens , when the slave trigger goes off

shootfirst

The 4.6V is at the canon flash side.

I'm afraid that I can't get a hold of any schematics. But as you said, connecting the 2 terminals of the flash makes it fire.

I'm not sure what the FET would accomplish. I have very little electronics experience. I'm trained as a Mechanical Engineer so I've had some exposure to electronics but not enough to understand your suggestion without further explanation.

That said, I think I am close to having a working solution with the parallel RC circuit, I'm hoping that I just need to dial in the values of the resistor and capacitor.

Any help is greatly appreciated.

Thanks,
shootfirst

williB

thats the easy part.
triggering the FET is going to be harder, without knowing what the slave flash trigger is doing..

Attached Images

canon_flash.jpg (19.2 KB, 210 views)

shootfirst

I'm not sure that we are working on this problem from the same perspective.

I have an optical trigger that shorts the two leads. I want to modify this trigger (not redesign a new one) so that it will work with my Canon flashes.

I've had some success with adding the parallel RC circuit but need help dialing in the behavior of this circuit so that it doesn't have such a large impact on the sensitivity of the optical trigger that I plan on using.

On the other hand, the optical trigger I have looks very simple (maybe only 6 or 7 components) and a total redesign would allow me to place the trigger and the additional RC circuit on a single PC board for a much cleaner installation. I'd try to reverse engineer the trigger I already have but it's potted in epoxy and could be a problem.

If someone has a schematic of a similar optical trigger circuit, I'd love to see it.

Thanks again,
shootfirst

shootfirst

I was just realizing that the circuit (multi flash slave) that was shared in a previous post in this thread could possibly be modified in such a way that I could take out the counter and keep the optical trigger portions.

If I wanted to start from scratch, perhaps someone could help me pull the optical trigger portion of that circuit out and ignore the counter.

Just a thought.