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Old 05/05/08, 10:58 AM   #7 (permalink)
giordano
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Join Date: 04/17/07
Posts: 317
Default Re: Tech question about DOF - macro environment

Quote:
Originally Posted by luigi bertolotti View Post
That is the problem... the above posted formulas include "magnification"... has it to be considered as the "magnification ratio" I achieve (the 1:2 of the example) or the magnification of the lens in itself, clearly related to focal length ?
m is the ratio between object size and image size: in your example, 0.5.

As ghammer says, the formula I posted is an approximation. It's good enough for everyday "macro" work.
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