Could a 500 series camera body or lens possibly be damaged by releasing the shutter independently of each other > fire the shutter on a lens while not mounted on a body or fire the camera without a lens? This might be done only occasionally to check each for correct functioning. I think I've read somewhere this may not be a good thing to do on some cameras possibly because the mechanism likes to have some resistance to "cushion" the action of the release. I do realize each will need to be recocked to mount.