Thanks for looking and commenting Chuck.
The 10 yr old book given to me with the Paph orchids used
illustrations obtained by flash at small apertures with an artificial
smooth background.
They were OK only but served the purpose. I would have been much
pickier, but it would not have been published until the next millennium.
As AG pointed out in the past, you know things are slow when the dof
thread appears.
Learned from Dr. focus long ago that FL has little effect on total dof,
but shorter FL have a greater percent in the rear--distal to the focal
plane.
The "absolute blur" as defined by the by the blur disk diameter of a
point in the background is larger for longer focal
lengths but the "relative blur" is the same--after adjusting for
different mag. Thus the longer FL background will be smoother as per
CH.
Part of this is also that the background area is more restricted by the
AOV.
A curious note in the Nasse article is that with distant backgrounds
the absolute blur is a f(physical lens aperture) and not really the
lens design.
Nasse frim Zeiss in his e-mail said an experienced photogs would
correctly ignore full wave dof solutions to their lenses (or something
to that effect)
so they don't provide them. So he was wearing his "I agree with Moose"
T-shirt that day. I have no clue why they do provide them for the
cine lenses.
Hope others liked the orchid. :-)
Trying to be in critical focus, Mike
--
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