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ovredal73
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p.1 #1 · C-mount to EOS conversion possible?

Sorry if this question is ridiculous, but I have to ask....

Is it possible to remove the mount off a C-mount lens and put an EOS mount on it? I am mostly afraid the image circle will be too small since it is meant for a very small 16mm movie negative.

http://cgi.ebay.com/Carl-Zeiss-Jena-DDR-LENS-TEVIDON-1-4-25-NOS-in-BOX_W0QQitemZ310091468660QQihZ021QQcategoryZ3323QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Oct 14, 2008 at 07:20 PM

jcolwell
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p.1 #2 · C-mount to EOS conversion possible?

The EOS register (or lens mount to sensor distance) is 44.0mm, and the register for the C-mount is 17.5mm. This means that to get proper focusing for the C-mount lens (i.e. as labeled on the lens), and especially to get "infinity focus", you'd have to stick the C-mount lens (44.0-17.5) = 26.5mm inside of the EOS body. It's possible that longer telephoto C-mount lenses might have enough "spare barrel" length to hack off 26.5mm or so, but not a small one like the shortie in the auction you linked. Of course, even if you get it to focus, then you'll still have to deal with the really small image circle.

Oct 14, 2008 at 08:45 PM

ovredal73
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p.1 #3 · C-mount to EOS conversion possible?

Haha. I need to read up on this register distance thing, so I can tell by myself before asking dumb questions. Thanks for the kind and patient explanation, Jim.

Oct 14, 2008 at 09:57 PM

scribble
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p.1 #4 · C-mount to EOS conversion possible?

Hm, quick question then. What is the register distance of the new Micro Four Thirds? This lens would be a nice alternative to the current 25mm F/1.4 option, the pana-Leica. As much as I enjoyed that lens, It is on the pricey side for an equivalent standard lens.

Oct 14, 2008 at 11:07 PM

ACElkins
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p.1 #5 · C-mount to EOS conversion possible?

I did see someone who mounted a 5.9mm Kinoptic Tegea on a Leica M8, had a little falloff on the corners, but its Big Brother, the 9.5mm Kinoptic Tegea is designed for 35mm cine film which is about the same size as APS sensors, so it should work as long as there is no mirror.

Might be some interesting conversions with the new "Micro 4/3rds" cameras comming out that don't have a mirror or pentaprism, relying on "Live View" instead. Believe the register distance is quite short for those cameras, so should be able to adapt anything. Would love to try my 5.9mm Angenieux, Kinoptic actually made a 1.9mm Rectilinear (!) wide angle for 16mm cine, might work on the Micro 4/3rds.

Oct 15, 2008 at 01:01 AM


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