I recently got a set of YN622C transceivers, along with the YN568 flash. I have some Canon 580ex flashes and one 580exII. I'd just like to confirm some things that I'm finding in my test as to how these will work. I have several camera bodies, the main one I'm testing with is a 6D since it has all the controls available.
My main question is in using the YN622, with the 580exII mounted on the camera and the YN568 off-camera, it seems that in eTTL mode, everything in channel one/group A, if I set the flash itself to FEC zero, then by setting the FEC on the camera menu, it is affecting both the flash on-camera the same. However, if I adjust the FEC on the 580exII flash panel itself, it seems to overide the FEC setting for the 580, and the FEC adjustment on the camera menu is only affecting the YN568 off camera. That is what it appears to me, is this correct?
Question #2: I've also been trying the 580ex (first version) on the camera mounted YN622. This flash seems to only respond to adjustments made on the 580ex flash menu, not from the camera menu. So to adjust the FEC for this flash, I have to do it on the flash itself, adjusting the FEC on the camera menu only affects the off-camera flash, am I seeing this correct? It's hard for me to confirm this visually. The other thing I've found, is that with the 580ex mounted on the camera mounted 622, I can keep it in eTTL and make FEC adjustments on the flash itself, while setting the remote off-camera YN568 to manual mode and adjust that flash independently. I tried this a couple of times, and once it didn't seem to work properly, at least I didn't seem to be able to change the 580ex output by changing the FEC on the flash, yet it remained in eTTL mode and the off camera flash was properly receiving manual flash power adjustments, but later I tried it again and it seemed to work. I tried this with two different 580ex flashes, so either one isn't working properly or I just didn't have it seated properly, perhaps. Either way, I did seem to be able to get this configuration to work (unlike using the 580exII which apparently I would have to go into mix mode to use it in eTTL while using the off camera flashes in manual). Am I correct in all this? I'm just trying to confirm what I'm seeing.