>I'm wondering, If I want to test my lenses, what film and
>lighting conditions would be the best?
Lighting? Flash. Eliminates the variable of camera/lens
vibration.
Film? For resolution testing, I'd probably go with Ilford PanF+
or Delta 100 or TMAX 100. Color film, I'd use Kodachrome 64.
One hazzard of using Fuji slide films for resolution testing is
the lateral halation that occurs in emulsion. This frequently
shows up in thicker emulsion films, such as the Fujichromes and
older B&W films. This lateral halation causes a bleeding of high
values into the neighboring low values.
I had downloaded a PDF of the USAF resolution chart and printed
five copies of it on photograde paper. These five charts were
then affixed to my wall (along with some grayscales and color
charts) and photographed. I happened to use Delta 100 and was
very pleased with how the test went. Would have preferred PanF+
due to slightly less bleed. The five charts were very important
because it showed serious flaws in resolving capability of one
of my lenses in the upper-left corner.
Doing resolution testing is a real eye-opener. Lenses that you
*think* are sharp, probably are not. They just have better
contrast. Contrast and resolution are NOT the same thing.
Using my enlarger, I ran it up to maximum magnification and
printed some 5x7s of the res charts from several lenses.
Catching where the line-pairs merge is a little subjective, but
when a lens is much better than another, it will be multiple
steps sharper than the others. An A+ grade lens, vs a B+ grade
lens is about four steps sharper in my system.
Yes, my 100/2.8 earned it's keep. I'm not revealing exactly HOW
SHARP it is, just that it exceeded all other lenses by a minimum
of three steps.
AG-Schnozz
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