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Text File  |  1992-12-31  |  2.1 KB  |  54 lines
  1. Newsgroups: rec.photo
  2. Path: sparky!uunet!psinntp!isc-newsserver!ritvax.isc.rit.edu!ANDPPH
  3. From: andpph@ritvax.isc.rit.edu
  4. Subject: Re: pinhole camera
  5. Message-ID: <1992Dec31.211049.29990@ultb.isc.rit.edu>
  6. Sender: news@ultb.isc.rit.edu (USENET News System)
  7. Nntp-Posting-Host: vaxb.isc.rit.edu
  8. Reply-To: andpph@ritvax.isc.rit.edu
  9. Organization: Rochester Institute of Technology
  10. References: <BzwME7.8LF@fc.hp.com>,<28178@dog.ee.lbl.gov>
  11. Date: Thu, 31 Dec 1992 21:10:49 GMT
  12. Lines: 40
  13.  
  14. In article <BzwME7.8LF@fc.hp.com> pdn@fc.hp.com (Paul Nuber) writes:
  15. >>When building a pinhole camera, what is the optimum size for the pinhole?
  16. >>I thought I read once that it was about 1/200th of the focal length.
  17.  
  18. A couple other formulas related to determining optimum pinhole diameter:
  19.  
  20. From Applied Photography, by Arnold, Rolls and Stewart:
  21.                         
  22.             D = SQROT 3.6vL    where v = pinhole to film distance 
  23.                                      L = wavelength of light used
  24.                                all in same units
  25.  
  26. From Materials and Processes of Photography by Stroebel, Compton, Zakia, Current
  27.  
  28.             D = SQROT v / 141  where D = pinhole diameter in inches
  29.                                      v = pinhole to film distance in inches
  30.  
  31.  
  32. From Ilford Manual of Photography
  33.  
  34.             D = SQROT v / 125  units same as in M&P book
  35.  
  36.  
  37. From Handbook of Photography by Henney and Dudley (1939)
  38.  
  39.             D = SQROT .00007v  where v = pinhole to film distance in inches
  40.  
  41.  
  42. happy new year!
  43. andy
  44.  
  45.      .....                                                               \
  46. .....|   |..                                                              \
  47.             | Andrew Davidhazy, RIT, High Speed Photography Lab.           \
  48.             :____________________________________________________ |'''''''\ \
  49.             : IN%"andpph@ritvax.isc.rit.edu"    fax 716-475-5804  |......./ /
  50. ____________:                                                              /
  51.                                                                           /
  52.                                                                          /
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