Fresnel Lens

Discussion in 'Large Format Cameras and Accessories' started by Marvin, Jun 26, 2011.

  1. Marvin

    Marvin Member

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    I noticed that the 45CX that I bought recently had a Fresnel Lens on it and I was wondering if it should be in front of or behind the ground glass?
     
  2. markbarendt

    markbarendt Subscriber

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    The ground side of the ground glass needs to be closest to the lens. The fresnel needs to be closest to you, it's just a magnifier to help you see the ground glass image better.
     
  3. holmburgers

    holmburgers Member

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    I have heard however that the fresnel does better on the side closest to the lens. You have to make sure you're focusing on the GG and not the fresnel though.

    This is just what another member has said, so I can't say from experience. In this situation the fresnel isn't actually magnifiying, but is evening out the light it receives.
     
  4. Neanderman

    Neanderman Member

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    The only way to know for sure on a given camera is to measure the 'T' depth to the GG. The ground surface of the GG needs to be the same distance from the ground class carrier's bearing surface as the film plane in the holder is from it's bearing surface.

    On my Crown Graphic, the fresnel goes between the lens and the GG.

    Ed
     
  5. Martin Aislabie

    Martin Aislabie Subscriber

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    I have an Ebony and my Fresnel goes behind the ground glass (ie the side away from the lens)

    The prisms also point away from the lens

    Martin
     
  6. ic-racer

    ic-racer Member

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  7. Dan Dozer

    Dan Dozer Subscriber

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    I have a Linhoff and the Fresnel is in front of the glass. However, I think most view cameras have it the other way around.
     
  8. Marvin

    Marvin Member

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    Thanks for the info and it is presently behind the GG.