One thing I have done to help with vision is to use a darkcloth when using my 645. Really amazing that it does help 'focus' (no pun intended) the image. Prefer to use a waist level finder for the same reason, feel more 'immersed' in the photograph than when using a 35mm.

Ed, much of what you say makes since, and we are all familiar with AA's Moonrise, if it were not for the fact that he knew his equipment, I feel that the image would not exist.