600ex-rt group mode

[jaayres20]

I have a quick question. I have 3 600ex-rt flashes and I have been experimenting with the group mode which I think is fantastic. I have one of my slave flashes set to group B and the other to group C. I am assuming that the master flash is group A? I don't see a way to change the group of the master flash on the camera. Anyone know if it can only be in group A or can you change the group of the master flash?

 

[hawkins132]

I've tried this too. So far my conclusion is: the Master is default to Group A, you can't change it. Keep in mind all groups are relative, I actually put group letter stickers on my 600 EX-RT to make it easier.