Old post office and customs house

Discussion in 'Pinhole Photography' started by ColRay, Dec 23, 2012.

  1. ColRay

    ColRay Member

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    I'm not sure the images form my latest camera are as sharp as they could be.

    So I have made a few changes

    The original set up was 90mm focal length with a 400 micron pinhole.

    I have now increased the focal length so it's now 112mm still with the 400 micron pinhole.
     
  2. cepwin

    cepwin Member

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    Looks nice...you did a good job!
     
  3. Jeff Kubach

    Jeff Kubach Member

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    Looks good to me.

    Jeff
     
  4. DWThomas

    DWThomas Subscriber

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    Lookin' good!
     
  5. PhotoBob

    PhotoBob Subscriber

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    Very well made image.
     
  6. Jim Jones

    Jim Jones Subscriber

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    It looks good to me, too. For a 400 micron pinhole and using PinholeDesigner with a user constant of 1.4, I'd try a focal length of 150mm.
     
  7. ColRay

    ColRay Member

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    Thanks Guys
    Jim I have had a look at the Pinhole Designer and the figures just don't add up. I'm not sure I understand the 'user constant' of 1.4 on the PD downloaded it shows 1.5 and the focal length is 129mm for the 400 micron pinhole
     
  8. Jim Jones

    Jim Jones Subscriber

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    You can set the user constant to whatever you want. I chose 1.4 based on testing for maximum sharpness in the center of the image. A larger constant favors sharpness towards the edges of the image at a cost of some sharpness in the center. There is more magic than math in pinhole photography. We can do whatever gives each of us the results we like.
     
  9. SMBooth

    SMBooth Member

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    That's a interesting little titbit Jim. Thanks, I learn more every day.
     
  10. ColRay

    ColRay Member

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    Thanks Jim:smile: