studio light 580 and 430s as friends

[Matt30D]

I recently had a problem with my master and slaves...I had my 580 master on my 30D camera and I had 2 430's working as slaves. Now I understand that there is a frequency that the 430's pick up to burst from the 580. My pics were really dark. I kind of understand that I should be shooting at 100 or 200 ISO, because the flashes are so bright...but why were my pics so dark. I had to shoot at 1/15 with a tripod to even get them close to be able to post-process, plus I was shooting in Raw. Is there are setting on these flashes so the image will be brighter? HELP@!!

[troutfisher]

Were you shooting on Av or M ? any FEC? can you post pics with exif data.

[Matt30D]

I was shooting in Manual mode.

[Matt30D]

My apertures were anywhere from 4.0 - 8.7 ish?

[Matt30D]

Do I need to adust settings on the master and slaves..My master was on Manual mode.

[troutfisher]

As I understand this-(and I am probably wrong and there are much better and more experienced brains than mine out there).If you put the camera on M at /or below the sync speed and the flash(s) on ETTL and use FEC as needed on the flash they fire a preflash and adjust the light output accordingly.At least thats what I do.

[PeteGB]

The master needs to be set to automatic. Automatic flash such as Canon E-TTL works by the camera firing a preflash and determining the exposure, it then fires the flash properly and quenshes the flash when there has been enough light produced.

If you set the flash to manual then the camera has no way of controlling the flash and the exposureis determined by the aperture (remember, shutter speed has NO bearing on flash exposure).