I don't quite buy that. What determines the size of the viewfinder image is the size of the frame the screen sits in (as long as we are talking +/- a millimeter). Make that frame a little bit larger and you have a 100% viewfinder. Of course, all elements that attach to the mirror box have to be 'accurate' but I don't see why that would be so difficult here. Even with a 90% viewfinder I would have hoped that what I see is from the center portion of the image, not from an edge...
I have always argued the *practicality* of any 100% viewfinder. A 95% finder already shows *almost all* of the image: 95% of 24x36 is 23.4x35.1 mm (for APS-C it is 23.5x15.7 vs. 22.9x15.3). No matter what application you are thinking of for either a negative or a slide, you will have a hard time actually *using* more than 95% of it. A slide frame will cut away about 7% and any lab (including home printing) will probably cut away more. In that sense it is *correct* to show 95% as it gives you a better indication of what you will eventually get than 100%. Sven Zitat von [EMAIL PROTECTED]: > > > > I believe the manufacturing tolerance of a 100% viewfinder is way too > > difficult and expensive. It is not difficult to understand why once you > have > > seen how the viewfinder is assemlbed. Every piece has to be 100% accurate > > (mirror, screen, pentaprism, eyepiece). Besides, even if the factory could > > do it at reasonable cost, the regional service centres can't. > > > > Alan Chan > > http://www.pbase.com/wlachan > > > > >This is probably a silly question which has been discussed to bits, but I > > >was wondering if someone could give me the quick answer as to why it was > > >too > > >hard to put a 100% viewfinder in the ist D (as opposed to the 90something > > >percent..) > > I think it might be too expensive. It might have other tradeoffs in > things like viewfinder image size. It's not impossible--most if not all > of Nikon's F-series pro cameras have 100% viewfinder coverage and I > believe at least one of their new pro digital cameras has 100% viewfinder > coverage. Shouldn't it even be easier given that the image area isn't as > big as the image area of film? > > OTOH, most Nikons have HUGE pentaprisms. That's not very Pentax-like. > > DJE > >
