The ST-E3-RT transmitter gives Canon the upper hand in the world of off-camera flash shooting. It eliminates the need for multiple accessories just to make your flash work off-camera. While I do have a few big gripes with it, like the lack of AF assist & no infrared signal, it’s still a wonderful step forward. If you’re using 600EX-RT Speedlites off-camera, you want this trigger.

One quick rant, because just looking at the picture doesn’t tell you this. The display screen and controls are on the top of the transmitter, which isn’t too big a deal. Just tilt the transmitter, because Canon was smart enough to make it pivot. WRONG! There is no pivot! Full control of off camera Speedlites is possible using the improved screen and button layout, but quick adjustments must be done by lowering the camera to waist-level to see the screen. Why Canon, why? It’s not a deal breaker by any means, but you will notice this omission.