CZJ Sonnar 2/85 Contax - my birthday present

[Orio]

Well, I received some money as gift this year from my relatives, and I was planning to just store it,
but while browsing around I stumbled upon this lens...





It's a Sonnar 2/85 in Contax mount. Not rare, but not so common to find either.
(for those who don't know, it's the "dad" of the whole Jupiter-9 breed).
At the price I found it (290 Eur, just CLAd, with two years guarantee, original case and a vintage Zeiss yellow filter on chrome mount
which alone is probably worth 40-50 Euros), almost impossible.
It's post-war, but one of the earliest batches, the date (september 1947) makes me guess with almost certainty
that it was made assembling parts made before the war, or in any case using materials stocked before the war. And, it's T, which most of pre-war copies are not.
The production of this lens by the Jena factory stopped in 1949, a good 10 years before the production of the Contax cameras in Stuttgart ended,
which is a sure sign (in my opinion) that the production stopped when the pre-war parts and materials stocks in Jena ended, and that they did choose to not
purchase new materials for what was a costly lens, probably too costly and elitist for post-war East Germany.
Well, to cut it short, I reserved it At worst, I can easily re-sell it, even with a profit.
I should get it early next week. So I'll finally have a good tele lens for my M mount cameras (via amedeo's adapter)
and of course, for my Contax cameras as well.

[twinquartz]

Nice one!
And nice relatives, too

[Orio]

[LucisPictor]

Congratulations, Orio!

What a nice present.

BTW, does the Amedeo adapter work well?

[Orio]

[fish4570]

well, happy birthday to you!

[patrickh]

What a catch and what nice relatives. Unfortunately I have cancelled birthdays for myself from lack of interest!


patrickh

[Attila]

One of the few lens what I want really, congrats!!

[hemmo]

What a birthday present!! Congratulations, Orio!

[tromboads]

..What they all said!

[Orio]

Thanks, I can't wait to try it

[Orio]

Note: I have edited the title thread to make it more google friendly, and moved the thread to manual lenses forum because I
add some technical content now.
I add here an image © by Marco Cavina that compares the MTF lines of the Contarex 2/85 Sonnar (optically identical to the
Contax rangefinder version, of course corrected for the different registration distance) and the Contax/Yashica SLR 2.8/85 Sonnar.
The image is taken from this very interesting article by Marco who compares the optics of the Contarex line with the more modern
followers in the Contax SLR line: http://www.marcocavina.com/articoli_fotografici/zeiss_contarex_mtf/00_pag.htm



As Marco states in his article, it's really about two different types of Sonnar lens. The Contax RF/Contarex lens is a true Sonnar type
with 7 elements in three groups, while the Contax SLR lens is more of an evolved Ernostar scheme (Ernostar was the predecessor
to the Sonnar type). In fact, the SLR lens is almost identical to the original Ernostar, with the exception of the last cemented group.

The performance of the modern SLR Sonnar is of course superior in terms of resolution (suffice it to compare the 40 lpm curves),
but it is interesting to note that the sagittal and tangential lines in the old Sonnar are much closer to each other, a clear sign that the
old lens is less affected by chromatic aberration. As Marco notes, the lower refraction glasses used in the Contax SLR version provide
a big advantage in resolvance wide open (although it is worth remembering that the SLR lens is one stop slower), but the down side
is the chromatic aberration that even at f/5.6 afflicts not only the 40 lpm curve (significantly already at half the lenght), but also the
20mm curve, which means that at the edges of the frame signs of CA become visible not only in the smallest details.

I find it curious and somehow ironic that these old lenses, calculated in a time when photography for most people was only B&W, show in fact a more
colour corrected performance than modern lenses made in a time when photography was mostly colour.

P.S. Note how well the old lens does in the 10 lpm lines, in spite of the single coating vs. the T* multi coating of the SLR lens!