Archived posting to the Leica Users Group, 1998/06/30

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Subject: [Leica] Optical tests again.
From: Erwin Puts <>
Date: Tue, 30 Jun 1998 18:47:35 +0200

Tom wrote:
>It is not a 'test' in so far that we do not use charts, optical benches,
>micro >contrast analysis or anything more radical than film and cameras.

May I add that all my tests of Leica lenses are conducted using benches,
graphs and numbers, sure. That gives them a much needed objectivity. I also
take all lenses through a controlled set of real life subjects and
lightning situations, using low speed transparancy and low/high speed B&W.
Using both methods in a complementary way, I can notice if, and when, where
the optical bench, MTF graph etc differ from the film results. Or more
common where the optical bench tells you that differences should exist,
where practical shooting fails to show them. Then I can revise my test in
order to make these differences visible. In this way, my technique improves
and, quite uniquely I think, can show the high level of progress made in
the last 10 years, which in normal shooting situations will not always be
The TriElmar is a case here. I have now read some tests in European
magazines, including FotoMagazin, which give a so-so or a good mark. Most
are little uninspired or lacklustre and fail to remark on the truly
outstanding characteristics of this lens. I only could reveal the real
imaging power of this lens after some study of the bench test figures and
conduct some appropriate practical testing.
It is the same as with highend audio apparatus. You need really demanding
music recordings in order to show/hear the fine differences in the sounds
from the speakers.