[Leica] 90mm recommendations

["Dante A. Stella" <dante@umich.edu>]

Here are some pictures taken with two of the greatest cheap medium teles
in M and M39.  These will be gone in a couple of days, so look now.   It
should open the eyes of some people here.

Benchmark your 90mm lens against the 90/2.8 Hexanon:
http://www-personal.umich.edu/~dante/sfida.html

Quite simply, any increase in resolution would be, for reasons discussed
in the page, invisible (if not impossible).  Ask yourself whether (1)
you have a better lens (likely, not) and (2) whether your output system
(to finished print) can maintain the same precision (even more unlikely,
given the multiple stages of imprecision involved).

I have heard various reports about the L 90/2.8 (current) vs. the K
90/2.8.  Some say L by a hair, some say K by a hair, some say too close
to call.  I think the difference in performance is strictly academic.
We can whip out our microscopes and TP, but really, both lenses are
already beyond what we can deal with getting to paper.  Personally, with
the K at 1/2 the price of the L, I'd grab the K.

- ------

And a sample 105/2.5 Nikkor picture wide-open:
http://www-personal.umich.edu/~dante/105test.jpg
(lens wide-open, approx 100m, focused, TMX in Diafine)
(you're looking at venetian blinds shot from across a boulevard).

This will, I think, show why Nikkors in LTM were killer lenses for the
1950s, and even now.  Not quite M-Hexanon/Elmarit-M class, but then
again, unless you regularly print over 16x20 (this section is 57x37
equivalent), you'd never know the difference.  You certainly won't with
conventional b/w films (as opposed to T400CN).  Maybe I just have a
really good one.  Who knows.  Maybe angels built 105/2.5 Sonnars in
Tokyo.

- ------

This exercise will also give you some ideas about how T400CN is much
more smooth-grained (but less contrasty) than TMX.  You also get 12-16
bits of tonal range, which should tax about any scanner.

Dante

main page: http://www-personal.umich.edu/~dante