JB> The slave flash seem to work with a digital camera like my Sony F717 - but JB> for slow speeds only - from app. 1/2 second and above! So it's no good for JB> digital portraits or things like that. For stills, it's fine, though (long JB> shutter speeds). Someone here might care to explain this digital flash JB> phenomenon to me?
Digicams use pre-flash not true TTL to measure flash output. So your pop-up flash flashes a litte bit before the actual exposure to measure the scene, than flashes the full exposure. It's fault of the cameras, not flashes. The optical slave sees the first pre-flash, so it triggers, but that's actually before the main exposure. Either use synch cord (there should be some even for the 717, doesn't it? It does have a hotshoe), or use a specialised digital P&S optical slave, like one from Metz - it has settings to flash on second flash, ignoring the preflash. fra
