IR Darkslide filter

Discussion in 'Medium Format Cameras and Accessories' started by Soeren, Jun 17, 2005.

  1. Soeren

    Soeren Member

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    Just a thought
    Is it possible to use/make an IR-filter that fits in the darkslide on the filmback.
    Ofcource it needs to be fitted in a way that prevent lightleaks.
    Can it be made thin enough ? perhaps not
    How about scratches and dust ? Could be a problem.
    Is it a problem that it is so close to the filmplane ?
    I have heard about fitting some kind of IR-filterfoil just behind the shutter in a 35mm SLR so I just thought.......
    Regards Søren
     
  2. glbeas

    glbeas Member

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    What an idea! I don't think it would be great for LF, it would scratch too easily, but on a Bronica or Hasselblad it would make for good shooting with the Maco films. I'd probably try to get the polyester filter, harder to scratch than the gelatin. Biggest concern is how rough the light seal would be on the filter as it is inserted into the slot and whether there would be any light piping through the edge of the filter.
     
  3. Soeren

    Soeren Member

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    I though of a dedicated IR-back. But how to fool the camera to allow the back to be removed when the shutter can operate (the pin in the real darkslide problem) ?
    Regards Søren
     
  4. gr82bart

    gr82bart Subscriber

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    I think you could modify a 'real' dark slide to hold an IR filter medium and defeat the mechanism that tells the Hassey a dark slide is in. I'll have to investigate this a bit, but this is a brilliant idea.

    Art.
     
  5. rbarker

    rbarker Member

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    On a Hassy magazine, I'd think it would be possible to simply tape a cut-down 100mm IR filter over the film gate. The darkslide would still slip in behind the filter, and function normally.
     
  6. Soeren

    Soeren Member

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    Nice. I don't think that's possible on the Bronica but then again I havn't tried.
    Regards Søren
     
  7. mark

    mark Member

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  8. glbeas

    glbeas Member

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    Inside the shell, when you pull the insert out, there is just barely enough room to tape a filter in place between the felt on my 120J back. The same can be done with the square format shells but the room for taping is a bit dicier. Only drawback I can see is the filter needs a tight fit against the insides of the film rails to keep white light from leaking around. I don't see a good way to get it under the edge of the rails. As far as taping it to the outside of the back I see the fit is very snug, hard to tell if it will interfere with the operation any. I'd try a very thin polyester filter there with no tape. It will not slip there and I think the extra thickness of the tape may pose a problem though I could be wrong on that point.
     
  9. Ronald Moravec

    Ronald Moravec Member

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    People add a Lee polyester ( similar to a gel, but tougher) between the film rails of 35mm slr cameras all the time. I would cover the darkslide slot with Mylar slide binding tape.