The basic tried and tested HYPERFOCAL formula needs to have a desired min. circle of confusion (cc) value entered to calc. the hyperfocal distance. However, most all the photographic world since the early 1900's discuss resolution in lp/mm. So if you know the min lp/mm you want to enter into the DOF equation, how do you convert from lp/mm to cc? Using QT's excellent post on this site, I took the diffraction limited values of both and backtracked the mathematical relationship between lp/mm and airy disc diam (cc), as I assume diffraction limited values produce only one resolution. And Diffraction seems to be a "common demonimantor" that pulls the two "units of measure" together, whereas we know the values must be equal.

fstop resolution limit.

N - R (lp/mm) - d (mm)

11 - 136 .014

16 - 93 - .021

22 - 68 - .029

32 - 46 - .042

45 - 33 - .059

64 - 23 - .085

Assuming these are equal values, the formula, 1/lp/mm * 2 would covnert lpmm to cc values. So if one wanted a min. of 23 lp/mm to record on film (leaving out 1/R and other issues for now) would the proper cc value entered into the hyperfocal formula be equal to

1 / 23 * 2 = .085

TYIA

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