[Leica] Lens performance and Photokina update

[Erwin Puts <imxputs@knoware.nl>]

EW wrote:
"How about a pattern of incompetence? There is no way that the competition
"can put a lens up against the 180 3.4 Apo Telyt and win, or even match it.
"Sure it costs a lot more for the little bit of difference. That was the
"wrong lens to use in this comparison on their part.

I am not in favour of CdI testing method. But to call these persons
"incompetent" or there ways of testing "incompetent" is not fair. At least
they base there conclusions on facts. These facts may be inadequate or
interpreted in a biased way. But they put them on the table and it is after
that anybody's own responsability to draw conclusions ar make decisions.
The 3,4/180 is a very good lens. It has no mythical qualities, nor is it
unbeatable.

On the 2/90 new:
No one has tested it in a real life situation. Only a few prototypes are
available at the moment, but these lenses are not up to the required
technical standards. Let us be a little bit cautious here. We all try to
get reliable info about this lens but it makes no sense repeating hearsay.
The old Summicron-M was at full aperture a bit weak. So is its sibling from
the R-line. Praising the R-Summicron 90  and denouncing the M-Summicron 90
for its full aperture performance is a bit difficult to understand.
The new one is a superior lens on paper. But let us wait for some
conclusive tests to answer the questions about the real life performance.

The topic why test reports and test methodology are not always in line with
perceived practical results is a matter of great interest and will warrant
a study  by itself. Watch this space for upcoming infoabout this theme.

The 35-70 new vario for the R. I gave the wrong dimensions as Dominique
pointed out. I did not mix them up, however but the press brochure had them
in the wrong order. But I blame myself for not being critical about it.

The new Delta 3200. I had long discussions with the designers at Ilford
booth. Again: preliminary info was wrong. It is not a  four layer emulsio.
but a one layer emulsion with four different types of core shell crystals
mixed in it. Every type is sensitized to a different 'speed'. The exact
composition and technique of this mix is an industry secret (I promised
not to give it away).  The result is an improvement of small area tonality
that really is impressive in comparison to TMZ. The real ISO speed of the
d3200 is (as I suggested) indeed =B1 1200 ISO. What happens when you push
develop is this: you get thin negatives with sa steep curve for the
midtones. That means in practise that the tonality of the grey tone areas
will suffer. (Same when you use a grade 5 paper on a normal developed
negative). The four core shell type technology restraints the breaking up
of the gradation in small subject areas and brings a subtle grey tone
gradation that the TMZ lacks.
Comparison pictures give the D3200 slightly finer grain and a bit better
dep shadow separation. A test in BJP howver notes that the TMZ has finer
grain. I wouldsya that it is a matter of developer and carefull technique
and visual expectations to be able to differentate between the two films.
The better one (in tonality at least) is the d3200. Even at EI 400 it is an
excellent film. ON a par with the D400. More to come after realtesting.





Erwin