Help! Lens separation on Kodak Bantam Special

Discussion in 'Camera Building, Repairs & Modification' started by Sethasaurus, Sep 19, 2010.

  1. Sethasaurus

    Sethasaurus Member

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    Just acquired a Kodak Bantam Special and after a lot of cleaning, noticed the lens to have what looks like rainbow-colored separation rings around the outer perimeter of the front elements.

    Haven't shot any film yet, so I guess I'm ahead of myself, but I'm wondering if I should go ahead and separate and reglue the lens elements.

    If anyone has experience with this type of repair, I'd appreciate some input.

    I don't have the precision levelling and centering equipment that the professionals would use, and I'm unlikely to spring another $135 (or thereabouts) to get someone to do it as the camera cost the same amount.

    I'd like this to be a usable camera and I'm fairly confident in my repair abilities, but you know how it is.. the first time you try something, there's always a risk, and I'd be unlikely to find an Ektar f2/45mm front group for sale on it's own.

    If anyone wants to send me a practice lens, go ahead :wink:
     
  2. c.d.ewen

    c.d.ewen Subscriber

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    I just had a look at my Bantam Special. You can unscrew the front cell, but I don't see an easy way of taking it apart. The VM shows it as a 6-glass Gaus, i.e., each cell has a single lens, an airspace, then a cemented doublet.

    I doubt that you're seeing separation. It doesn't look like a rainbow. What you may be seeing is a naturally forming lens coating.

    In any case, if it's at the edge, it won't affect your photos. Go get some of that unperfed film and blast away!

    Charley
     
  3. Sethasaurus

    Sethasaurus Member

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    Thanks Charley.
    So far I've taken the approach of doing as little as possible! It does bug me though.. I'm not a perfectionist, and I could probably get away with stopped-down shooting, but it's kind of a fly in the ointment.
    I think the decoration ring is supposed to unscrew, so I may just have a closer look, at least.
    I've got some film on it's way.
     
  4. clayne

    clayne Member

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    If you can't see the effect it's not an issue unless you make it one.
     
  5. Ian Grant

    Ian Grant Subscriber

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    I have an early Rodenstock Sironar with quite noticeable separation and that rainbow effect is quite typical, it's there on two similar aged Rodagon enlarger lenses where separation is also present..

    In the case of this Bantam lens as it's at the outer edges it's very unlikely to have any effects at all on the image quality.

    Ian
     
  6. Sethasaurus

    Sethasaurus Member

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    OK, I soaked the group in alcohol and managed to finally unscrew the decoration ring and remove the front element.

    The rings actually come in about a third of the diameter of the lens (a little more than what you see here). Not a great pic (my cellphone is the only digital camera I have..).

    The separation is between the 2 elements at the back and it looks like the edge of the aluminium housing needs to be turned off to remove the lens.
    I'm thinking about doing that and separating & recementing, although my film might arrive first :wink:
     

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  7. mhcfires

    mhcfires Subscriber

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    If you have film on the way, why not try it the way it is before possibly screwing it up. Might be worth the wait.