20x24 Pinhole Camera hole size

Discussion in 'Pinhole Photography' started by Swordfish, Aug 15, 2006.

  1. Swordfish

    Swordfish Member

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    Hey Folks!

    I wanted to know if anyone has any experience working with a 20x24 pinhole camera.

    Basically need to know a good starting point for pinhole size that would cover a sheet of 20x24 that is not curved , and I prefer a look that simulates an image one would expect from a 30 in. lens on that format...so slightly longer than normal.

    Thanks in advance !

    Michael
     
  2. Pinholemaster

    Pinholemaster Member

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  3. tpersin

    tpersin Member

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    Michael-
    you can check out mrpinhole.com for a fairly nice online pinhole calculator from which you can determine angle of view, pinhole size, focal length, etc. and, there's always the f295 forum (all lensless imaging welcome)

    http://www.f295.org/Pinholeforum/forum/Blah.pl/Blah.pl?
     
  4. Swordfish

    Swordfish Member

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    Excellent ! Thanks very much.
     
  5. Jim Jones

    Jim Jones Subscriber

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    My favorite downloadable pinhole calculator is free at PinholeDesigner. For optimum sharpness in the center of the field I suggest a user constant of 1.5 with this program. Pinhole photography generally favors wide angle pinholes over the longer ones due to the laws of optics. For example, a 15" focal length pinhole can resolve 1.4 X finer detail on the negative than the 30" one. However, it will have more falloff in both sharpness and illumination towards the corners of the image.