A we all know, when you turn on the M7 the first thing you see is the ISO of you film setting. I always set my ISO manually so I can push or pull according to light conditions. Then when I turned on the meter I would see 200 or 800 ISO. Now it only shows the ISO of the film canister (400) no matter where I place the wheel on the back of the body. How did that happen? How do I "turn off" the DX reader? It is not set to DX.