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  1. #1

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    Correcting barrel distortion in wide angle lenses

    Some of my wide angle lenses have some distortion, probably 2% barrel distortion. How do I correct for this distortion when I am printing in the darkroom?

  2. #2
    David A. Goldfarb's Avatar
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    Well, I suppose you could try pinning the paper to a pincushion shaped pillow, but I've never heard of anyone trying to correct this kind of distortion at the enlarging stage.
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  3. #3

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    Quote Originally Posted by David A. Goldfarb View Post
    Well, I suppose you could try pinning the paper to a pincushion shaped pillow, but I've never heard of anyone trying to correct this kind of distortion at the enlarging stage.
    wouldn't that make the corners out of focus?

  4. #4
    David A. Goldfarb's Avatar
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    That's probably why no one tries to correct this at the enlarging stage, though you could stop down and try your luck.

    Another option might be to enlarge through a lens that has the opposite degree of pincushion distortion, but enlarging lenses are usually designed to be free of distortion, and a lens that isn't designed as an enlarging lens could have other problems when used in this way (e.g., impractical to mount, falloff of illumination, not terribly sharp, etc.).
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  5. #5

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    Do what the old timers did. Use the taking lens as an enlarging lens. This was not an uncommon practice. Of course, mounting a modern SLR lens to an enlarger might pose some problems. Easier, but not necessarily easy, to do with prime lenses. Forget about doing it with a zoom lens.

  6. #6

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    Quote Originally Posted by fschifano View Post
    Do what the old timers did. Use the taking lens as an enlarging lens. This was not an uncommon practice. Of course, mounting a modern SLR lens to an enlarger might pose some problems. Easier, but not necessarily easy, to do with prime lenses. Forget about doing it with a zoom lens.
    cool i'll try that!!! i'm a DIY guy so mounting an SLR lens isn't an issue for me.

  7. #7
    David William White's Avatar
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    OMG, you MUST post these. Print with your normal enlarging lens and again with your camera lens.

    It's real late, and half my brain says it will cancel out and the other half says it will make it worse.

  8. #8
    AgX
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    The procedure of using the taking lens as enlarging lens could compensate for light fall off in a n/p process.

    However any distortion would get stronger...

  9. #9
    Jim Noel's Avatar
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    Printing a negative made with a lens having barrel distortion with an enlarging lens (or same camera lens) having barrel distortion will only double the effect. The only real solution is to replace the camera lens with one not having this problem. If is is an extreme wide angle lens, the barrel distortion is expected.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

  10. #10

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    any enlarging lenses that have pincushion distortion? maybe that would cancel the barrel distortion.

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