Thanks for your replies!
AdamJ- by that token, if I stick with my 580EX and get a 430, i would use the 430 for "fill" correct?
And instead of the ST-E2, would it not be cheaper for me to get the 90EX flash to trigger the other flashes? or will i lose some control there?
I figure that way i can have a small carry around "pop-up" flash for my Mkiii for emergencies (i know there is very little light from these)
I've just realised that my previous post didn't properly address your question.
My previous suggestions were made on the premise that, for family (group) portraiture, two off-camera flashes would give you much more flexibility and control than one, hence the suggestion to add:
- an ST-E2 and one more flash, or
- two more flashes. In this scenario, the two new flashes would be off-camera, controlled by the 580EX II on the camera - usually in non-flashing mode so that it doesn't contribute to the exposure. Or
- three YN-622s and one more flash
The 90EX is indeed another option that I overlooked. I believe it would give you the same functionality as the ST-E2, albeit without the ST-E2's external controls so you would need to use the camera's flash control menu.
For what it's worth, for family portraits I use two Yongnuo 565EXs, a YN-468 II and four YN-622s. The third flash enables background lighting or a hair light, etc.