Modifying Lens Mount

Discussion in 'Canon EOS' started by brent_bennett, Jun 19, 2011.

  1. I do not have a digital camera yet, but if I get one I want to use my Contarex lenses. None of the models (such as NEX and Olympus) appeal to me (adapters are made for Contarex lenses for them). The question is: If I get a Canon digital SLR body, are there particular models that have mounts that are not plastic, can be removed fairly easily, etc. A Rebel XT is available to me for modifying; is that as good a choice in that regard as any of the newer ones? This will be a machining job, and obviously I will be limited to using lenses without autofocus, so I need a camera body that will accomodate manual focus and f/stop/exposure settings.
    FYI: the lens register on my lenses is 46mm, and the Canon body register is 44mm. Plus, of course, the body must be modified to accept the unusual Contarex lens mount.
    Thank you for your suggestions.
  2. Brent,
    2mm should give you enough to convert a Contarex-Olympus converter to a Contarex-EOS adapter. Just get the Contarex-Olympus and any mount-EOS, have them both machined down and then joined. There is a guy on Filkr who has done that to FD-EOS to work on teles that focus beyond infinity.
    All EOS cameras have metal lens mounts and they all come off easily.
  3. How would you control the aperture?
  4. Most of your questions were answered on almost four years ago, Brent (see link). Here's the most pertinent answer you received then:
    The Contarex mount was notoriously difficult to use on any other camera. I doubt you'd find any such adapter, not the least of which because the Contarex lenses don't actually have aperture controls (they're on the camera). Usually such conversions require a lot of machining and the donation of a lens mount from the camera to adapt the lens to.​
    Since Contarex lenses don't have aperture rings, and they are able to "communicate" only with Contarex bodies, you'd be limited to shooting wide open. To me, it sounds like a lot of trouble for very little benefit.
    If you want to shoot with manual focus lenses on an EOS digital body, why don't you pick up a Carl Zeiss Jena or two (or one of their Soviet clones, a Jupiter or Helios) in M42-mount? M42>EF/EOS adapters are cheap and plentiful.
  5. You posted a similar question in 2008, and I doubt if any new options are now available. Even if you could get some surgery done on a Canon body to allow a Contarex lens to mount on it, you would still have the problem of how to set the aperture, The Kipon micro-4/3 adapter has an aperture ring, and this is possible because there is a large difference between the Contarex and micro-4.3 registers. That's not so with Canon bodies – even if the EF mount itself were replaced, the housing in which it sits would almost certainly not leave room for an aperture ring.
    Olympus are not the only people who make micro-4/3 cameras. Some of the alternatives seem to be highly regarded, for example those from Panasonic – although I have no personal experience of such cameras. I am pretty certain you would be far better off buying a Kipon adapter and a micro-4/3 body rather than undertaking the expensive and almost certainly doomed attempt to adapt a Canon body.
  6. You posted a similar question in 2008, and I doubt if any new options are now available.​
    But there are new options available. Contarex to Canon was a small thing, of interest to a handful of people. Nikon to Canon is a big thing. Nikon produced a lens, the 14-24mm f2.8 AF-S G (whew! too many letters) that far, far, far and away outperforms any Canon wide. (Ya listening, Canon?)
    The Nikon G lenses are like Contarex lenses, their aperture is controlled by a mechanism on the back of the lens. So' people figured out how to build, in the 2.5mm difference in the Nikon 46.5mm and Canon 44mm registers to build an adapter with a lever that engages the Nikon G mechanism. Such an adapter could be built to do the same for Contarex. I don't know if the existing Contarex to NEX or Micro four thirds adapters have such a mechanism that you can adapt to your project, or if you'd have to go to some bright camera technician and say "here, do something like this for me", but it's technically quite feasible.

Share This Page