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Phil Davis |
9:20 11 Oct 04 |
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Larry Francis |
18:04 11 Oct 04 |
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Depth of Field Calculator in EXPO-DEV |
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Sandy King |
20:24 16 Aug 04 |
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In doing some research on depth of field calculations I found that the limits of human vision are given as anywhere from the size of an object that would subtend one minute of arc to one that would subtend twenty seconds of arc. In practical terms, assuming a print size of 8X10 and a viewing distance of 8X10, these different limits correspond to, on the non-critical observation to a circle of confusion of about 0.18 mm, which approximates minimum negative resolution on the film of about 5.5 lppm, to a very critical observation that would correspond to a circle of confusion of 0.063 to 0.045, with negative resolution on the film of from 16 - 22 lppm.
The premise is that most people looking at an 8X10 print at 325mm would perceive a loss in image quality if resolution dropped below about 5.5 lppm but that virtually no one would be able to perceive an increase in image quality with resolution of over about 20 lppm.
My question is this. What size circle of confusion for a print of 8X10" size is built into the depth of field program in Expo-Dev?
Sandy King
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David Rude |
15:22 17 Aug 04 |
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Sandy King |
17:18 17 Aug 04 |
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Jorge Gasteazoro |
21:34 25 Jul 04 |
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Robert Sfeir |
15:30 23 Apr 04 |
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Robert Sfeir |
15:32 23 Apr 04 |
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Robert Sfeir |
15:47 23 Apr 04 |
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Paul Sfeir |
12:17 3 May 04 |
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