Sheer Wall is a pretty camp that earns you decent mileage for day one of your canyon trip. There are groover locations located up or downstream. The kitchen fits in nicely towards the back of the camp, tucked against the sheer cliff wall. We found an area for our chair circle downstream from the kitchen. You probably want to keep this to yourself, but ATT gets a single bar of service here.
If you camp here, see if you can spot the Idaho rock, pictured below.