Just a short post about camera flashes and trigger voltage.
Canon specifies a safe trigger voltage up to 6 volts using the hotshoe on their digital cameras. If it’s higher, it might damage the camera. So I have measured the trigger voltage on two older flashes I have lying around, since I didn’t get (m)any hits searching the interewebz.
Pentax AF-330FTZ has a trigger voltage of 3.14V
Hanimex 325AZ has a trigger voltage of 110V
So the Pentax AF-330FTZ should be safe. Hanimex 325 however, isn’t. What’s kind of scary is that I have used the Hanimex on several occasions on my 350D. Luckily no harm done (as far as I can tell).
Update: Found this web page explaining some more around this issue.
I take this to mean that all Canons DSLRs newer than the 350D, as well as all the professional models, can use flash with trigger voltages up to 250 volts in their hot-shoe. However, 6 volts is the safe limit for the D30, D60, 10D, 300D, and Canon’s digital compact cameras.