LTM Lens Cleaning/Repair

Discussion in 'Camera Building, Repairs & Modification' started by Fotoguy20d, Jun 26, 2009.

  1. Fotoguy20d

    Fotoguy20d Subscriber

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    Does anyone have instructions or a website link for help in disassembling an LTM lens to clean internal surfaces? I have a 50mm f1.5 Xenon with some haze and dust as well as a good sized black sliver (presumably peeled paint) that I'd like to clean up. Before I just start pulling out screws, I'm hoping someone can tell me how to do this.

    Thanks,
    Dan
     
  2. Fotoguy20d

    Fotoguy20d Subscriber

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  3. John Koehrer

    John Koehrer Subscriber

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    Since it's a LTM lens, It's pretty simple.
    The decorator ring at the front unscrews & the front element or group will simply drop out.
    It should be obvious which direction the first element faces but be careful to note the following elements.
    It's possible to install them backwards.
    If the group falls out as an assembly it's easier but if you take it apart note how the elements face.
    Same thing for the rear. There usually a spanner ring to remove & everything should fall out.
     
  4. Fotoguy20d

    Fotoguy20d Subscriber

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    John,

    I'm not sure what I"m supposed to remove on this lens. There doesn't seem to be anything to grab onto to unscrew. On my 50mm Elmar, there's a spanner ring front and back. Here, nothing that I can see. When you refer to the decorator ring, do you mean the black one with the identification information? There isn't so much as an indentation in it and with the curvature of the lens I don't know how to grab onto it.

    Dan
     

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  5. John Koehrer

    John Koehrer Subscriber

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    Fotoguy,
    Yes, The decorator ring is the one with the information on the front of the lens.
    Get a rubber stopper at the local hardware. Take the lens with for sizing. When you have the stopper press it against the ring and push counter clockwise. If the element protrudes too much you may have to gouge out a depression in the stopper to clear the glass.
    Sometimes I've used PVC pipe with an O ring to get a stubborn one apart.
    On the back there's probably a spanner ring under the mount but I'm just guessing on that one. Look for a set screw around the base.
    I don't know what the three screws in the mount are holding but if you approach it carefully you shouldn't have problems reassembling it.
    Take some notes & pictures as you go along for reference.
     
  6. Fotoguy20d

    Fotoguy20d Subscriber

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    This is a stubborn one. I've had no success so far. I contacted Essex Camera (www.camerarepair.com) and they quoted me $108 to disassemble it and clean it out. Anyone have any experience with them? Not that I've given up yet.

    Thanks,
    Dan