I expected APS or 4/3's. Instead, it appears to be a NEW format
produced by Kodak especially for Leica. In effect, Leica said
niether 4/3s or APS is good enough!
Actually, it's an old format, developed by Kodak, but not especially for Leica. Leica has been using it for years, in their Modul-R digital back, so anything other than that format would be something new for Leica.
Now, elsewhere in this thread, you added:
My statement saying I expected the M8 to be built around either APS
or 4/3s is built around two things. One, I think either are good
enough for a camera of similar quality. I was unaware that Leica
felt that either size format would compromise the output quality of
existing legacy lenses.
personally, I don't care about existing
legacy lenses, so I guess I don't care about that issue all that
much.
But Leica isn't catering to you, they're catering to people who already own Leica film systems. But that's neither here nor there...
I'd still like to see what kind of DRF camera could be built
around these formats.
I don't know how familiar you are with either lens design, or rangefinders. I'd assume not very familiar with either, from your comments.
So, to fill you in...
A rangefinder doesn't view through the shooting lens, it views and focuses through a viewfinder and rangefinder system that has two windows on the front of the camera, near the top. In order for this to happen, the lenses must be relatively small, otherwise, you can see the taking lens in the viewfinder. I assume you've either seen a Leica rangefinder in use, or at least seen pictures. Did you notice the weird cutouts on the back of lens hoods? That's so the viewfinder can see through part of the hood from the back, reducing the amount that the lens hood intrudes into the viewfinder image.
Rangefinder wide angle and normal lenses are symmetrical (or nearly so). Aside from leading to very sharp, low distortion optics, the symmetry makes them as short and narrow as possible. Reducing length and diameter keeps them out of the viewfinder's field of view. The wider the lens's field of view, the shorter it needs to be to keep out of view.
Four thirds (tm) lenses are not symmetrical. In fact, to achieve Oly's ideas of telecentricity, they're less symmetrical than any other SLR lenses in production. This makes them very large for their field of view. A Leica 21mm f2.8 Elmirat is 43mm long, and 57mm in diameter. The Oly 11-22mm f2.8-3.5, in comparison, is 93mm long and 75mm in diameter. You wouldn't be able to see around that lens in the viewfinder of a rangefinder, unless you made a very big rangefinder, 30mm wider and taller than an M. And it's not just a zooms vs. primes issue, an Oly 35mm f3.5 has a greater diameter and length than a Leica 30mm f1.4, despite the Leica being nearly three stops faster.
Next issue is that rangefinder lenses must couple the lens's focusing mechanism to the camera body's rangefinder mechanism. In existing rangefinders, this is done mechanically: you focus the lens, and a cam on the back of the lens moves the camera's rangefinder mechanism. For four-thirds, it would have to be done electronically. I don't know if the Olympus rangefinders transmit focus distance information back to the camera accurately enough to use for a rangefinder. I do know the Sigma four thirds lenses do not.
And the last issue is intended use. Rangefinder users are street shooters and event shooters. Cartier Bressan and "The Decisive Moment", all that sort of jazz. The four thirds patents advise against lenses faster than f2.0. The Leica line contains five different lenses faster than f2.0, including a 50mm f1.0. Voigtlander makes 3 more. People shoot the dang things wide open, indoors in dim light. The classic Leica shooter uses pretty high speed films. That's one reason Leica opted for a sensor twice the size of four thirds, an extra full stop of low light shooting ability.
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Normally, a signature this small can't open its own jumpgate.
Ciao! Joe
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