BP writes:
"Let's remember, before this gets too clouded. A 50 mm lens has the
same dof
as a 100mm lens, if the 50 is cropped to the same coverage area as the
100."
Well almost but not quite. Even with the thin lens assumption the FL
term for near and far limits of dof do not fall out. The distribution
of the dof changes with a higher percentage of the dof distal to the
plane of focus with shorter FL's. Not really much shift at the 50 and
100mm choices but pick something wider and there will be a larger
difference. Dr. Focus concurred with this from a post a year or two
ago.
Would be thrilled to see a full wave dof calculator for even one
complex lens--perhaps ping Zeiss.
Skeptical about thin assumptions, Mike
http://www.cambridgeincolour.com/tutorials/depth-of-field.htm
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