I asked Zeiss to comment on the possibility of lens specific dof tables
for some of their lenses especially given the white
paper by Nasse stating that the thin lens approximations for dof
"should not be taken too seriously." Dr. Nasse himself responded.
They do provide full wave calculated dof tables for cine lenses--see
below---- but not otherwise, for reasons that are not clear to me. He
stated that the calculated tables
would apply to the center area if any field curvature were present and
subtle errors in focusing or manufacturing flange to sensor/film
distances could easily
overwhelm the effects. He by no means denied that lens design per se
can affect the dof with all other factors being equal.
I did a few checks on the lenses below and there are some differences
with the usual dof formulas. I could not easily extract the pdf data
into excel
where it would be easier to try and discern what factors lead to the
largest differences from the usual dof calculators.
Trying to Escape the Black Hole that is the CoC for dof, Mike
http://tinyurl.com/28qqhqq
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