Originally posted by sterretje limitation is that the K5 can't do iso 50
I have tried all the combinations from ISO 100 to 1600 in the table provided with the instruction manual linked above, and I can't tell the difference in exposure looking at them in-camera (I photographed my bookshelf from across my darkened office). I also went beyond, to ISO 3200 and f22, and things looked okay there too. Results for f/2.8 and ISO 80 were near enough to everything else that I don't feel uncomfortable using that in future (naturally more trials will be needed).
The next thing is to see what happens when the flash is nominally out of range and compensatory amounts of aperture are dialled in. I don't expect stellar results here, but it should be fun!
---------- Post added 05-22-15 at 11:53 AM ----------
Originally posted by Lowell Goudge trigger voltage is between center pin and the shoe contact (side rails)
be careful wit multi meters, many low cost ones have variable input impedance as a function of range, and can load the trigger and give false, (low) readings
The measuring was done by a professional who works in hospital biomedical engineering, so I think I can trust the competence of both the device and the person using it. I also showed him the instructions from the article quoted above before we started, so we've got it as right as we possibly can.