Fun with Leicas (the kind that drives you nuts)

Discussion in '35mm Cameras and Accessories' started by David H. Bebbington, Mar 19, 2008.

  1. David H. Bebbington

    David H. Bebbington Inactive

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    I recently had the bright thought of using Leica R lenses on Leica M and screw-thread bodies. I therefore bought 2 Novoflex adapters. One is called LEM/LER (Leica R lens to Leica M body). It is approx. 19 mm thick. I have tried it by putting a piece of ground glass across the film gate of a Voigtlander Bessa T (film gate more accessible than Leica M2). It seems to work. So far so good.

    I then bought a Novoflex LEI-F adapter (supposed to be Leica R lens to Leica screw-thread body). This is approx. 10 mm thick. I tried this on a Bessa L. The image is out of focus. Not so good.

    I find here
    http://www.graphics.cornell.edu/~westin/misc/mounts-by-register.html
    that Leica R register is 47 mm, Leica screw 28.8, Leica M 27.95, so the screw adapter should surely be 18.2 mm thick. Before I return the screw thread adapter, I just wanted to ask if people think that this has simply been assembled wrongly in error or if it actually does something - I can't think what!

    Regards,

    David
     
  2. Lee L

    Lee L Member

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    I haven't used the Novoflex adapters, so I can't advise on the problem other than to say your surmises appear to be correct on the screw mount adapter. As you likely know, there's a 1mm greater film-to-flange distance designed into the M mount to allow screw mount LTM adapters to function, so the R lens to LTM adapter should be 1mm larger than the R lens to M mount adapter.

    Steve Gandy at cameraquest.com used to sell an R lens to M body adapter that had a "focusing" ring/scale to drive the RF mechanism in the M body. You could "focus" the ring, take your distance reading from that adapter scale, and translate the reading to the R lens. However these are no longer available new, and I suspect rare used.

    Lee
     
  3. David H. Bebbington

    David H. Bebbington Inactive

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    Thanks for your reponse Lee. Just for the record, the relative thicknesses are the other way round - if you think about it, an R lens to LTM adapter plus an LTM to M-mount adapter should together be the same as an R lens to M mount adapter, so the R lens to M mount adapter on its own should be fractionally bigger. Anyhow, it's back to the drawing board with the LTM adapter - I shall be interested to hear what the factory have to say.

    Regards,

    David
     
  4. Lee L

    Lee L Member

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    David,

    Of course you're right, the M body is thinner to accomodate the adapter + LTM lens, so the R to M mount adapter needs to be 1mm longer than the R to LTM adapter. I was in too big a hurry when I posted earlier today, preoccupied with getting errands done and picking up my son from school.

    I posted mainly to make you aware of the adapter with the rangefinder drive mechanism. Good luck finding what you're looking for.

    Lee