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Thread: WICH HOLE DIAMETAR

  1. #1
    Senior Member
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    WICH HOLE DIAMETAR

    Hi
    I need help.I have 2 pinhole objective.One have 135mm,second is 85mm.I need advice wich hole is good for this focal lenght.
    Thanks for answer

  2. #2

    WICH HOLE DIAMETAR

    It depends on what you want. But to make it short, you can use a simple formula for a first approach:

    pinhole diameter [mm] = sqrt (focal length [mm]) / 27

    This gives for the focal lengthes you mention

    135 mm: about 0.4 - 0.5 mm
    85 mm: about 0.3 - 0.4 mm

    Good luck!

  3. #3
    Senior Member
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    WICH HOLE DIAMETAR

    Thanks for answer.

  4. #4

    WICH HOLE DIAMETAR

    The subject of best pinhole diameter has been hotly debated for over a hundred years. Several free downloadable programs let one quickly determine the diameter without math. Perhaps the most vertsatile is www.pinhole.cz/en/pinholedesigner/. We can spend much time arguing about the subject, or making and testing pinholes. We can slso use whatever pinhole is convenient, and enjoy making photographs.

  5. #5

    WICH HOLE DIAMETAR

    Quote Originally Posted by 1198
    The subject of best pinhole diameter has been hotly debated for over a hundred years. Several free downloadable programs let one quickly determine the diameter without math. Perhaps the most vertsatile is www.pinhole.cz/en/pinholedesigner/. We can spend much time arguing about the subject, or making and testing pinholes. We can slso use whatever pinhole is convenient, and enjoy making photographs.
    And then go shorter than the 1,9 Lord Rayleigh, e.g. 1,5

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