"Tom Reese" <[EMAIL PROTECTED]> wrote: >Bill Robb wrote something that I snipped until this was left: > >> The Canon rep told me (sorry, not compelling evidence, just anecdotal) >> that they felt accuracy and reliability would be improved by eliminating >> moving parts, as much as possible, and that in the long run, it would be >> cheaper for manufacture and, consequently, for the consumer to purchase. > >The accuracy comment makes sense. With an aperture ring you have detents for >stops and half stops. Anything in between is a guess. Electronic aperture >operation gives the photographer more precise control.
Accuracy is certainly part of it. Almost all cameras are electronically controlled now, but you have to convert the electronic information into mechanical movement at some point. The closer this conversion is to the final mechanism, the fewer mechanical linkages you'll have in between and the better off you are. Also, having part of the mechanical system for aperture control in the camera body has a big (negative) effect on manufacturing and assembly costs; purely electronic stuff is much cheaper to assemble than mechanical/electronic stuff. This was, despite opinions to the contrary, a large part of the reason for Pentax ditching the potentiometer and aperture cam from their camera bodies. Canon and Minolta have got almost all the mechanical stuff except the shutter and mirror eliminated from their camera bodies and it pays big dividends in manufacturing costs. Pentax (and Nikon) would undoubtedly like to eliminate the stop-down lever and mechanism from their camera bodies but I don't see how they could do it without a wholesale lens mount change like what Canon & Minolta did. If that happens we'll have some *real* lens mount issues! -- Mark Roberts Photography and writing www.robertstech.com
