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Paint Can Pinhole

  • 05-10-2009 12:02am
    #1
    RCNPhotos
    Closed Accounts Posts: 601 ✭✭✭


    www.paintcancamera.com

    I was lookin at these thinking "Wow, I want one, how much?", and couldn't find a price. Took me a minute to realise why would I buy one when I can make one.

    Now my question is, for the hole, where could I get that done? To be .5mm, or as close as possible? Any ideas where or who could do that?


Comments

  • #2
    Ghost Train
    Registered Users, Registered Users 2 Posts: 30,404 ✭✭✭✭Ghost Train


    What you could do it cut out a large hole in the can, then take some aluminum from a coke can sand it down on each side and use a needle to make as accurate and smooth a hole as you can. Then attach it over the large hole.


  • #3
    RCNPhotos
    Closed Accounts Posts: 601 ✭✭✭RCNPhotos


    that could work actually yah, nice idea


  • #4
    DaireQuinlan
    Registered Users, Registered Users 2 Posts: 6,704 ✭✭✭DaireQuinlan


    RCNPhotos wrote: »
    www.paintcancamera.com

    I was lookin at these thinking "Wow, I want one, how much?", and couldn't find a price. Took me a minute to realise why would I buy one when I can make one.

    Now my question is, for the hole, where could I get that done? To be .5mm, or as close as possible? Any ideas where or who could do that?

    If you're exposing onto something as large as a sheet of photo paper then it doesn't have to be too small. Like everything else, you can get as technical with this stuff as you like :D Image quality wise, pinholes are a tradeoff between too large which results in a blurry image, and too small which results in excessive diffraction and a soft image. The second bit can be solved to some extent by exposing onto as large a piece of film or paper you can find for a given pinhole size. This is why 35mm pinholes generally look a bit crummy.

    There's actually an optimum pinhole size for a given focal length to minimize the above. IE its the ideal balance of softness due to diffraction and softness due to the size of the pinhole. Its format agnostic, hence the admonition above to use as large a format as possible. In this respect something like an 8x10 in a paint can is ideal.

    Here's a calculator that calculates the ideal pinhole size given a particular focal length:

    http://www.mrpinhole.com/holesize.php

    Some other good resources and examples there aswell.


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