I've just bought myself a Canon G9 in an attempt to break myself into the digital world from film.
I read on one forum that you couldn't plug an external flash unit (as in Balcar, Bowens etc) into the hot shoe mount via sync cable because of something to do with the flash voltage frying the innards of the G9..has anyone else heard this?
I was wondering then (if so), the way round this would be to use a wireless transmitter mounted on the G9 hot shoe to hit the receiver/slave on the external flash unit.....?

My old Balcar units are working fine on a Canon 5D. I use an adapter on the hotshoe to plug in the sync cable.

the Canon Speedlight Transmitter ST-E2 works like a charm on the G9.

There is a six volt sync trigger limit for the G9, explained here
http://www.botzilla.com/photo/G1strobe.html

I've list some known compatible external flashes here
http://lightdescription.blogspot.com/2008/...flash-list.html

and there are many more.

Pocket Wizards and Cactus (usually called cheap Ebay and worse) wireless remotes are known to work with the G9.