Having trouble with the 600 rt in group mode. I have two 600 rt's and a 5d mk3....I have been trying to use these in group mode with limited success. I was trying to use the groups in ettl mode. My on camera flash is the master and the off camera is set to group B. I adjust the master flash compensation right on the camera control. I kept it at no compensation...now I adjust the compensation on the slave via the master flash panel....it took almost two neg stops to keep it from blowing out the subject which is a white bowl. It definitely does dial down the slave....but the settings never actually show up as changed on the back of the slave lcd. When I set the slave to manual mode and change the settings...they DO change on the back of its lcd...is this normal?
