Steve's Digicams Forums

Steve's Digicams Forums (
-   Flash (External) (
-   -   420EX avoiding preflash to use Op. Slaves (

matthew2000tx Jul 20, 2008 12:32 AM

I have a Canon 20D & 420ex. I ordered a optical slave studio kit, but I'm having trouble figuring out how to put the flash in the manual mode to turn off the pre-flash that the 420ex does to meaure exposure. My slaves keep going off with the first flash before the picture is taken. The saves are just basic AC slaves with no PC cord connections, and no way to adjust lenght of flash time.

Thanks in advanced. I'm new to studio stuff

VTphotog Jul 20, 2008 8:19 PM

There are slave which are specified as 'digital', meaning they will ignore the pre-flash, and trigger on the full flash. I believe that some may also be switchable for either way. If yours aren't, than it may be that you will have to use your camera with manual settings to prevent the pre-flash, or you may be able to disable it in your camera menu rather than on the flash unit.


All times are GMT -5. The time now is 7:42 AM.