>Not if you are inadvertently touching the shutter release (or >AF-ON button)
Lets see. Left hand finger pushing the release button. Right hand rotating the lens. The third hand growing out of my back touching the shutter
> >I don't understand your insistence on this point - it takes >just a moment to switch the camera off, so why not just be >safe?
Because it is unimportant. What is important is not to think about it and change the lens as quickly as possible so I don't miss the shot. Since I have done thousands of time and I have never, ever read about ill effects I would certainly say that turning camera off while changing lenses is trivial. If you feel better, go ahead and turn camera off. I certainly will not.
> >As others have mentioned, it's not as if you have never >encountered an odd problem with your equipment...
The problems I encountered related mostly to Nikon QC.