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ColRay

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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.
 

Jim Jones

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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.
 
OP
OP

ColRay

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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
 

Jim Jones

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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.
 
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