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  1. #21
    Maris's Avatar
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    The best holes I've ever seen are the single hole electron microscope grids I used in a variety of transmission electron microscopes. These apertures are made by etching and are close to perfect at a molecular level.

    The sharpest looking pinhole pictures tend to exploit high contrast high frequency detail that is just coarser than the limiting resolution of the pinhole itself.
    Photography, the word itself, invented and defined by its author Sir John.F.W.Herschel, 14 March 1839 at the Royal Society, Somerset House, London. Quote "...Photography or the application of the Chemical rays of light to the purpose of pictorial representation,..". unquote.

  2. #22
    Jim Jones's Avatar
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    Quote Originally Posted by Mike Walker View Post
    Hi Wild Bill
    Mike Walker here I make the Harman Titan pinhole cameras, acid etched holes are superior to laser holes, and if done the right way they very very round, I am going to upset some here, put round does not matter that much, it is more the sharpness of the inside edge of the hole.
    I can back this up, as Schneider once had a play with this, and by taking 3 scalpel blades interlocking they and blacking with candle smoke made what they said, was as sharp a pinhole as it was possible to make.
    Hope this helps.
    Mike
    Sharpness in pinhole images is limited by diffraction at the edges of the pinhole. The triangular pinhole has greater edge length in relation to the opening area than does a circular pinhole. However, there is one advantage to a triangular pinhole; by moving only one blade the aperture can be varied. With more care, a four-sided variable pinhole can also be constructed.

  3. #23

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    I'm no expert, but I was talking to a man recently who made large format pinhole chromes, and he used acupuncture needles of hair thickness. IIRC he used taught metal foil.

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