In article
,
DaveC wrote:

Is there any reason an "economy" flash (Achiever 630AF) will work on a film
camera but not on a digital camera. I've been told this but see no reason for
it to be so.

The destination camera is Canon PowerShot G9.


As mentioned by J. and Ryan, some older flashes were directly fired by a
mechanical switch contact in the camera. They may have too high an
open-circuit voltage or short-circuit current for use with cameras that
fire the flash electronically.

If you do a web search for that specific flash, you may find
specifications for it. It might have been sold as being compatible with
a particular camera. If it claims to be compatible with Canon EOS
cameras, it probably would work with the G9.

What if it is safe to use, but does not communicate with the G9's
electronics? If the flash is claimed to be "automatic", you can
manually set your camera's f/stop according to a calculator on the flash
body.

You also might be able to use it in completely manual mode. Set the
camera's shutter speed to something less than the maximum flash sync
speed. Then calculate the camera's f/stop based on the flash guide
number, camera ISO setting and the distance from flash to subject. The
flash may have a calculator for that too.

Fred