Material on the lens Carl Zeiss Jena Tessar 1: 3,5 f = 7,5cm especially for Radozhiva prepared Rodion Eshmakov.
The lenses used to create this article are provided by Alexander Korolev.
This article is dedicated to Carl Zeiss Jena Tessar 1:3,5 f=7,5cm (hereinafter simply Tessar 75/3.5) – standard lens of medium format cameras, in particular Rolleiflex twin-lens reflex (TLR) cameras. Tessar f/3.5 lenses are described in US1849681 1931 by Ernst Wandersleb and Willy Merte. Essays from the history of the development of Tessar lenses are presented here и here. Also on the site there are already articles about faster versions of the pre-war Tessar: Tessar 75 / 2.8 и Tessar 80 / 2.8.
Specifications:
Optical design - 4 lenses in 3 groups, "Tessar";
Schematic diagram of the lens from US1849681.
Focal length - 75 mm;
Relative aperture - 1: 3.5;
Estimated frame format - 60 × 60 mm;
Aperture limits - 1:3.5 - 1:16.
Aperture device - 14 petals, stepless adjustment;
Features - the lens presented in this article did not have its own focusing mechanism.
Design and adaptation
The lens itself is very small, light and compact. The body is made of aluminum, not brass, as was the case with lenses from the first half of the 1930s. Of the controls, this instance has only an aperture setting ring with a marked scale. The lens did not have a focusing mechanism, but an adapter made by someone once was screwed onto the M42 thread - the lens was probably used in a photographic enlarger or some other similar installation. The appearance of the lens is shown in the photo below.
Thanks to the large rear focal length, lens adaptation is easy. In order to be able to take photos with this Tessar 75/3.5 and a Sony A7s camera (E mount), I just had to screw it into an M42-M42 macrohelicoid of suitable thickness, add the M42-EOS and EOS-NEX adapters.
Optical properties
The Tessar 75/3.5 doesn't offer any surprises: the lens forms a soft image at wide f/3.5 due to residual spherical aberration, with apertures up to f/5.6 and beyond it gets really good sharpness.
Since this old Tessar 75 / 3.5 has uncoated optics, the overall image contrast is noticeably worse than with older single-coated lenses like Triplet 78 / 2.8. Moreover, non-coated lenses are often exposed during storage to atmospheric moisture, the action of volatile acidic components, which leads to clouding of the optics of many non-coated lenses. Due to the stronger scattering of short-wavelength rays in comparison with long-wavelength ones, on defects in the surface of the lens lenses, when shooting under normal lighting conditions, you can notice a bluish veil, which can be partially overcome by lowering the proportion of the blue channel in the shadows. The lens itself has almost neutral transmission.
From an artistic point of view, the lens is the most classic tessar, maybe not the most interesting. Industar-26m 50 / 2.8 I like more both in terms of parameters and in the picture. The lens performs best on a frame format close to the calculated 60 × 60 mm, so I took almost all the pictures with this lens as "shiftoramas" using shift adapter.
Together with this lens, I also got a lens similar in optical design and similar in parameters from a photographic enlarger Industar-90U 75 / 4, which was produced in 1986 at LZOS (and, by the way, it is still produced for technical needs!). I took several shots under equal conditions using Tessar 75/3.5 and Industar-90U to evaluate the effect of enlightenment on the formed image. It was of little interest to evaluate sharpness, since Industar-90U is designed for finite distances, and Tessar 75 / 3.5 for infinity. And, by the way, it is so clear that the Soviet Industar in 1986 did not go far from 1931 in terms of technological level.
Below are shots on Tessar 75 / 3.5 and Industar-90U, made as "shiftorams".
I did not find any significant difference in the sharpness of the lenses in these pictures, but it is clearly visible that the frames from the enlightened Industar are noticeably more contrasting and have more juicy colors.
More examples of photos taken on a full-frame camera Sony A7s using shift adapterare listed below.
Conclusions
For its age, the Tessar 75/3.5 is a good lens - "a classic of the Tessar genre", but its parameters are boring, and the optical quality is rather weak when used on small format cameras. This lens is best used on medium format cameras. Better yet, get a post-war Tessar 80 / 2.8 T or try an interesting Soviet Industar-26m.
You will find more reviews from readers of Radozhiva here.
A couple of questions.
1) Does it make sense to “pair” medium format lenses with speedboosters? In order not to mess with shift adapters, for example. Yes, the same Mitacon introduces a small amount of spherical aberration, i.e. this will no longer be a test of the lens, but is this influence so great against the background of what the lens itself gives out?
There is a sense, only there are no boosters for SF-> FF. Or simply not. The booster should be much better than the lens that is attached to it. This is the problem - find and try such a booster.
2) Is it possible to apply at least one layer of enlightenment myself? Heard about etching in acetic acid.
You can, but etching is a fig method. And even deep-coating or spin-coating are far from the easiest ways. Because you can apply anything, but what needs to be applied is not a one-time experience, but a technology. In general, I am already puzzled by this question.