C/Y Zeiss 50mm 1.7 Back Focus

Discussion in '35mm Cameras and Accessories' started by photomat-, Nov 21, 2011.

  1. photomat-

    photomat- Member

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    Hi,

    I have a C/Y Zeiss 50mm 1.7 that has a back focus issue. Wide open at closest focus, the shift is off by about 1cm which is nearly 0.4 of an inch. Can anyone recommend somewhere I can send the lens for a CLA/service to get this fixed as I am getting tired of missing shots and it's my favorite lens. Any idea of approximate cost?


    Thanks in advance.

    Matt.
     
  2. ic-racer

    ic-racer Member

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    I'm not sure I understand the issue.
    Even if the infinity stop on the lens is off, it should focus fine at close range. When you snap a picture, does the focus jump to different setting?
     
  3. Rol_Lei Nut

    Rol_Lei Nut Member

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    As above, could the issue be with the camera body?
    Do other lenses focus properly?

    P.S. Saying where you are could help if you want tips for repairpersons.
    Otherwise, people will assume that you are from the Center Of The Universe and let other people from the Center Of The Universe answer you....
     
  4. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    I visited his webpage and He is from Las Vegas.

    Umut
     
  5. photomat-

    photomat- Member

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    Sorry, I thought my location was listed on the side. I am in Las Vegas.

    The issue exists whether I use a Contax body or an adapter on an EOS body. And at different focusing distances. I have no issues with a Tokina 28mm or a Zeiss 28mm.
     
  6. Rol_Lei Nut

    Rol_Lei Nut Member

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    Still don't understand: is the image in the viewfinder focused but the result unfocused? Or does the distance scale not correspond to reality?
    In the latter case, unless you're scale-focusing, how does it ruin shots?
     
  7. TimVermont

    TimVermont Subscriber

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  8. photomat-

    photomat- Member

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    The image focuses in the viewfinder but the result is the focus is behind the area I focused on. So if I focus on the 20cm mark on a tape measure, the resulting focus is at 21cm or so. I took a great portrait of my niece where I focused on her eyes, the result was the side of head was in focus.
     
  9. photomat-

    photomat- Member

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    Thanks for the link, I'll check them out.
     
  10. naaldvoerder

    naaldvoerder Member

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    If this happens in, for example a Canon 5D, with adapter, it most likely means that the focusing screen is not "justiert", not placed at the right hight. Canon apperently presumes, that people with a AF camera do not need a properly placed focusing screen. Canon sellls a set of 10 "shims" to do this yourself. If this happens in a Contax body you may want to check if the mirror has not slipped downward from its metal frame. Apperently after some 20 odd years, the glue that hold the mirror in place losens up and the mirror can slip down. I think this is a known problem in the RTS and RTS@ and maybe other bodies. In a proper SLR what you see on the focusing screen, is what you get on the filmplane, even if the lens does not focus on infinity.
    If you need more info on the Canon shimming, give me a call, i did this procedure on my 5D..

    Jaap Jan

    P.S. I think the focusdepth in the 28mm lenses is not shallow enough to show up the problem.
     
  11. Rol_Lei Nut

    Rol_Lei Nut Member

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    +1

    Also think it's a mirror or screen position problem
     
  12. photomat-

    photomat- Member

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    Focalpoint gave me a guesstimate of $125 plus return shipping. I am having a hard time thinking that it is a screen / mirror problem on both cameras I am using it on. I need to find another Contax body to test with. Mine is a 167MT btw.

    Thanks.
     
  13. ic-racer

    ic-racer Member

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  14. ic-racer

    ic-racer Member

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    Most people would have a hard time thinking that the lens shifts focus during the exposure then shifts back when the mirror comes down. But maybe it is somehow that you are holding the camera causes it to do that.
     
  15. photomat-

    photomat- Member

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    How would that happen?

    Umm, no. It is a consistent occurrence. For further confirmation, I'll check with a tripod when I get a chance.