20x24 Pinhole Camera hole size

Swordfish

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Joined

Jan 26, 2005

Messages

5

Format

8x10 Format

• Aug 15, 2006

• #1

Hey Folks!

I wanted to know if anyone has any experience working with a 20x24 pinhole camera.

Basically need to know a good starting point for pinhole size that would cover a sheet of 20x24 that is not curved , and I prefer a look that simulates an image one would expect from a 30 in. lens on that format...so slightly longer than normal.

Thanks in advance !

Michael

 

Pinholemaster

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Joined

Oct 17, 2005

Messages

1,566

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Westminster,

Format

8x10 Format

• Aug 15, 2006

• #2

http://www.pinholeresource.com/

These guys are a good source for info.

 

tpersin

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Aug 17, 2004

Messages

170

Location

Pittsburgh,

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Multi Format

• Aug 15, 2006

• #3

Michael-
you can check out mrpinhole.com for a fairly nice online pinhole calculator from which you can determine angle of view, pinhole size, focal length, etc. and, there's always the f295 forum (all lensless imaging welcome)

http://www.f295.org/Pinholeforum/forum/Blah.pl/Blah.pl?

 

OP

OP

Swordfish

Member

Joined

Jan 26, 2005

Messages

5

Format

8x10 Format

• Aug 15, 2006

• #4

Excellent ! Thanks very much.

 

Jim Jones

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Jan 16, 2006

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Chillicothe MO

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• Aug 15, 2006

• #5

My favorite downloadable pinhole calculator is free at PinholeDesigner. For optimum sharpness in the center of the field I suggest a user constant of 1.5 with this program. Pinhole photography generally favors wide angle pinholes over the longer ones due to the laws of optics. For example, a 15" focal length pinhole can resolve 1.4 X finer detail on the negative than the 30" one. However, it will have more falloff in both sharpness and illumination towards the corners of the image.