Flash Problem!!!!!

I know I have read about this somewhere before but after much searching, I can't find a solution anywhere. I have a Genesis monolight being triggered by an on camera (5D) flash (580EX in master mode). I am also trying to trigger a 430EX on slave mode. Using the 580 as a triggering flash dialed down to 1/128th power, the Genesis fires but not the 430. I get markedly underexposed shots, pretty much just black. I take the 580 off the hotshoe and turn the speedlights off, plug sync cord into 5D and monolight, exposure is fine. Any clue as to what I am doing wrong. I assume that the 580 on the hotshoe is changing something automatically in camera which is otherwise set to manual. Please help me!

When the 580EX is mounted in the hotshoe and set to Master mode, it fires a command signal to the slave before the shutters open. This "preflash" causes the Genesis monolight to fire prematurely and doesn't have enough time to charge up before the main flash from the 580EX fires. Hence, it doesn't contribute to the lighting of the picture. The 430EX won't fire either because the command signal from the 580EX is "drowned" out by the premature firing of the monolight. So, it also doesn't contribute anything to the shot. The 580EX at 1/125 power doesn't contribute much either. And that explains the almost black frame.

Adding optically triggered slaves into an ETTL wireless configuration always leads to problems of one type or another.

I was afraid of that. So am I screwed as far as being able to use the 580 and/or 430 as secondary lights? Is there another way? Or do I need to just buy a second monolight?

Thanks for the input!

You can just use the 580 and 430 on manual instead of ETTL.

Clif Moore wrote in post #6523261
I was afraid of that. So am I screwed as far as being able to use the 580 and/or 430 as secondary lights? Is there another way? Or do I need to just buy a second monolight?

Thanks for the input!

You can use the same setup but instead of triggering the monolight optically, use a PC sync cable or an RF remote module.

bsaber wrote in post #6523300
You can just use the 580 and 430 on manual instead of ETTL.

I think that's exactly how he has it set up since he did say that the 580EX was set to 1/128 power.

Ah, misread that.

PacAce wrote in post #6523372
You can use the same setup but instead of triggering the monolight optically, use a PC sync cable or an RF remote module.

Right, but that still means I can't use the 580 or 430 as secondary flashes in conjuction with the monolight unless I can trigger them in some way that causes them to flash while on manual and without the delay I get when I trigger them using their built-in IR system. I might be able to acheive this by hooking them up with optical photo-slaves. I would need some hotshoe brackets with pc sync's as well. Suddenly a second Genesis monolight ( only $190 with shipping discount ) seems affordably attractive. Hmmmm....

The 580EX and 430EX don't work well with optical slave attachments. But almost any flash that isn't a Canon EX model will. See what you can find used and cheap (hopefully with adjustable manual power), hook it up to a slave sensor and you're in business.

Thanks guys. This all gives me lots of options to consider. Thanks for helping a big noob!

Clif Moore wrote in post #6523627
Right, but that still means I can't use the 580 or 430 as secondary flashes in conjuction with the monolight unless I can trigger them in some way that causes them to flash while on manual and without the delay I get when I trigger them using their built-in IR system. I might be able to acheive this by hooking them up with optical photo-slaves. I would need some hotshoe brackets with pc sync's as well. Suddenly a second Genesis monolight ( only $190 with shipping discount ) seems affordably attractive. Hmmmm....

I'm confused by what you're saying. I thought your initial setup had the 580EX mounted on the 5D as the master, the 430EX off-camera as ETTL wireless slave and a monolight triggered optically? If so, what I was suggesting was to connect the monolight to the camera via a PC sync cord or RF remote units. The 580EX and the 430EX can still work the way you had it before, as the master and the slave, respectively.