Mon 20-Feb-12 04:14 AM | edited Mon 20-Feb-12 04:14 AM by TomCurious
The plus of the in-camera DX mode (compared to later cropping): The camera meter uses only the DX area, so a bright highlight outside of the DX area won't affect the exposure.
The minus of the DX mode (compared to later cropping): You are locked into the center crop. If you shoot the FX frame and crop later, you have more image at your disposal to crop from. I.e. in case a piece of your subject is cut off by the edge of the DX frame, you're out of luck. If you shoot in FX mode you can adjust the crop later.