How is this an argument against an electronic aperture simlator as opposed to a mecahnical one? It is in fact possible to make an aperture ring that electronically controls the F-stop used during exposure. I guess this can even be done without an aperture simulator. A "thumb wheel" on the lens, so to speak. Prefereably a "hard to move" wheel.
To me it's not important WHERE this controle is located. What is improtant is that it's not unintentionally moved. The thumb wheel on the body is prone to accidently being moved away from the wanted setting - or electronicaly overruled by some uncoprehesible flash automatics. The thumb wheel is easily moved unintentionaly. A very simple way to fix this would be to make it work in a way, that it has to be pushed forwards (into the body) before it can be moved. Or perhaps I just need a "HOLD" button, to secure my aperture setting. (Like the HOLD button on the MZ-S holds the shutter speed). To me this would be exactly as good a an aperture ring. Except for the fact, that I own some excellent lenses without an A-setting = no body controle available. When using a flash I can: 1) Use Manual Mode and use the green button - preset to activating the SPEED (Tv) according to the ambient light - to set the the proper speed. This can be done with non-A lenses. 2) Use Program Mode (PF=Hyper Mode ON in the PF dialog; meaning that the green button function is constantly ON in "P-mode") and then preselect the aperture on the body. This requires the A-setting on the lens. If I had a HOLD APERTURE button I could make sure my aperture setting stays until I change it. Until I get a button like this, I prefere an aperture ring for flash photography. Jens Bladt Arkitekt MAA http://hjem.get2net.dk/bladt -----Oprindelig meddelelse----- Fra: Mark Roberts [mailto:[EMAIL PROTECTED] Sendt: 26. september 2005 14:37 Til: [email protected] Emne: Re: Temporarily enabled with 2.8/70-200mm "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
