I have the following:
- Nikon D3100 (max 250V trigger voltage)
- Vivitar 2600 flash (148V trigger voltage*)
- Yongnuo YN465 flash (6V trigger voltage)
- Hot shoe universal translators**
I'd like to use both flashes wired up through the hot shoe translators. I know that my camera tolerates the trigger voltage of the 2600 on its own, but I'm not sure about the YN465 if everything is wired together.
My concern is that the translators may connect all the positive terminals together and all the negative terminals together, so that the circuit gets closed solely by the camera on trigger. This would mean that the YN465 will receive the 2600's 148V on its positive terminal (while it's producing 6V), and then when the flash triggers, the YN465 will receive 148V on its negative terminal too, when the circuit closes.
I know the camera can handle that, but I'm not sure the YN465 will be okay.
So my question is: Should I be worried about this? As I see it, there are some possibilities/options:
- The YN465 can tolerate the extra voltage.
- The YN465 can't tolerate the extra voltage, but the translators detect and relay trigger signals (and can tolerate 148V on a node). I can't imagine they do this given their price and number of connections, and they would probably need an internal power source for their internal relays/switch circuitry.
- The translators just hardwire everything together, making it an unsafe setup if the YN465 can't tolerate 148V. A Safe-Sync adapter on the 2600 should work here.
- Use a wireless or optical trigger for one of the flashes, thus removing any direct electrical connections.
My instinct tells me that 3 & 4 are the only safe options.
* I measured my own 2600 at about 38V, but I'll play it safe and assume the higher voltage is possible.
** Or something similar; I don't actually have these yet, otherwise I would be able to do some measurements on my own.