Sharpness (Zeiss Otus 55mm, f/1.4 APO)
Of course I want a sharp lens but the more I work with lenses the
less I am concerned about ‘absolute’ sharpness, whatever that is.
There are a lot of very fine sharp lenses available in the Nikon
mount or that can be converted to that mount. Most of the lens es
mentioned in Book Two of this series, plenty “sharp enough” for
good macro work.
And sharpness is not the only consideration. A lens can be very
sharp but difficult to use for other reasons; it can be too sensitive
to light or the widest aperture doesn't give enough light in the
viewfinder, etc.
Sharpness can also be a matter of opinion to a degree. You will
know when you find what ‘you’ consider a sharp lens. And my
own investigation into sharper and sharper lenses ended in the
factors that obscured sharpness from appearing, like diffraction
of course, but more subtle yet were the various kinds of
aberration, distortions that blurred or obscured sharpness.
In the last analysis sharpness became for me a study of APO
(Apochromatic) lenses, literally a matter of the distortions of color,
the way color can be messed with. In a word, my search for
sharpness left me looking at lenses with less and less distortion so
that I could better see whatever it was I was calling sharpness.
Eventually sharpness became an almost meaningless word to me
because the only lenses I used were very sharp and that
‘sharpness” turned on subtle coloring, finally a matter of personal
taste. Interesting?
Anyway, sorry to take you on a sidetrack, but for the record I just
thought I should point out a little about my journey to sharpness.
