Ag writes:
The comment was made that DoF and Hyperfocal calculations are based on
a binary decision: It's either sharp (in focus) or it isn't. I highly
disagree with that assessment.
One could say the state of focus could be covered in one bit as long as
it is a qubit--thus something can be can be in or out of focus and even
both at once. Using superdense coding involving quantum entanglement
even more possible states are possible with one qubit.
Even Dr. Hubert Nasse, senior scientist at Zeiss admits DOF and tables
thereof are a fuzzy concept. Further complicating the matter
are the neareast and farthest range of DOF and hyperfocal distances
assume an ideal thin lens. This is clearly not the case. Zeiss does
indeed
provide tables with full wave solutions for their cine lenses so they
must be of some use. They do not provide them for their other lenses
and I asked why.
http://www.zeiss.com/camera-lenses/en_us/cine_lenses/master_lenses/master_prime_lenses.html
They provide them for coc of .013 and .025mm.
Here are the 0.013:
http://www.zeiss.com/content/dam/Photography/new/pdf/en/cine/master_lenses/mp_feet_13.pdf
I think Dr. Focus looked into where one lens differed from the ideal
and by how much a couple years back. Thus the perceived/real dof can
indeed differ using different lenses. Microcontrast, field curvature,
exact focus distance all are important variables affecting real or
perceived dof. Nasse has said a photographer uses these principles as a
general guide but experience is more important than full wave solution
tables.
I am not sure why they seem to be useful for the cine lenses though I
have seen clips of a focus puller at work and it was amazing how he
could gauge exact distances by eye.
Exactitude requested for fuzzy concept, Mike
--
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