used by almost everyone in this area of photography that I have
met. Almost all of my close-up/macro lenses don't even have auto-
focus, so there is no choice. I never use auto-focus except, as
mentioned, when chasing critters around, which I seldom enjoy
anymore.
In my approach to lenses for macro and close-up work sharpness
has been important. I want the lens to be as sharp as possible.
Originally I went to the great lens testers and studied what they had
to say. As it turns out "Sharpness" is not an exact term. It is
somewhat loosely defined and seems to be made up of a
combination of resolution and acutance (edge-contrast). I got into
that for a while, but found that some lenses, like the legendary
Zeiss 100mm (and 50mm) Makro-Planar lenses, while pretty
"sharp," were what I told myself somehow too "contrasty" for me. I
liked more of a matte finish, whatever we could agree that is.
When I tried to talk about it with owners of the Zeiss Makro-Planars,
they did not appreciate what I had to say about their lenses, even
though I myself owned them too. But I had to trust my my own
eyes, so I persisted in my search for "sharp" lenses. To make a
long story short, what I found out (and all on my own) was that
apparently what I was seeing or picking up on was a lack of lens
correction in the Zeiss Makro-Planars. These are not highly-
corrected lenses in terms of aberration, and so forth.
In time I discovered that apochromatic (APO) lenses, another
loosely defined term, were perceived (by me) as sharper. In other
words, they were the kind of sharpness I had always been
searching for. Apparently, these finer corrections (APO) removed
some of the chromatic aberration (purple fringe) and other distortion
just enough so that my experience of photos shot with them was
satisfied as far as sharpness goes. Take aware that purple fringe,
etc. and the color perceptively improved IMO.
Now I was onto something and began to hunt down and test APO
lenses. Unfortunately the time and effort to correct a lens to APO
levels is expensive, like: very expensive. Nevertheless, I sold off
what I needed to, saved my pennies, and began finding and
purchasing apochromatic lenses. And the important part is that, at
last, I was very satisfied as far as color and sharpness were
concerned. As they say, "who woulda' thunk it?"