View of the ISCO-Gottingen Westron 35 / 2.8 lens, examples of photographs from it, and the review itself especially for Radozhiva, prepared Rodion Eshmakov.
ISCO-Gottingen Westron 35 / 2.8
Features ISCO-Gottingen Westron 35 / 2.8
Optical design (presumably!): Similar to Schneider Curtagon 35 / 2.8 (view)
Field of view angle (in full frame): ~ 60 deg.
Aperture Limits: F / 2.8-F / 16
Aperture design: 8 blade, with preset mechanism
Filter thread: 49 * 0,75 mm
Mount: M42
Case Material: Plastic, Duralumin
Production: West Germany, 60s.
Design features
ISCO-Gottingen Westron 35 / 2.8 is a member of the family of low-cost wide-angle lenses manufactured by ISCO-Gottingen, a subsidiary of the renowned Schneider Kreuznach. That is why (and, of course, in terms of optical properties), it can be assumed that the lens design is identical to that of the older Schneider Kreuznach Curtagon.
The budget of the lens mainly lies in its design: plastic parts are widely used (like that of another brand - Enna Munchen), which makes the case less resistant to mechanical damage (small dents, scratches remain; the applied paint peels off). How much did the pedantic Germans save on durability and reliability - history is silent, but due to the use of plastic, the lens has a huge drawback: the mechanism for setting the aperture "freezes" at temperatures below +5 tightly due to thermal compression of the aperture rings (once, apparently, tanks froze in about the same way). And it's definitely not about lubrication - the focusing ring functions unchanged.
ISCO-Gottingen Westron 35 / 2.8
In general, the design of the aperture preset mechanism looks a bit wild: you need to press the spring-loaded button while moving the ring to the desired mark. After that, it is assumed that both rings rotate together to close the diaphragm. Again, here we encounter a difficulty - the preset ring has no notches, and the installation has only ¾ non-saggy corrugation due to plastic due to plastic.
The focus ring is quite convenient: grasping and wide enough. But it rotates counterclockwise, and not clockwise, as usual. What again guided the gloomy Teutonic genius?
Only one external part is made of metal - this is the mounting flange, which has a corrugation for more convenient screwing the lens onto the camera.
An unpleasant moment is the protruding rear lens of the lens:
ISCO-Gottingen Westron 35 / 2.8. At infinity.
ISCO-Gottingen Westron 35 / 2.8. At MDF
Most likely, without finalizing the rear, this lens will catch on to the mirror when focusing on “infinity” on full-frame SLR cameras. When focusing on MDF, the rear lens “leaves” the vest with the lens block into the body.
The lens’s MDF is convenient - ~ 0,28 m (the ring is marked up to 0,3 m, but goes further), although this is not a macro mode.
When focusing, the lens block moves completely without rotating:
ISCO-Gottingen Westron 35 / 2.8
ISCO-Gottingen Westron 35 / 2.8
It is seen that at infinity the front lens is well protected by a pseudo-blend.
ISCO-Gottingen Westron 35 / 2.8 has an eight-petal diaphragm with rounded petals - it gives subtle octahedrons from point light sources. Petals, although matte, but still light.
Summary: the lens construct is generally unsuccessful, especially when used in the cold season, due to poor-quality housing materials and strange technical solutions.
Optical properties
The optical design of the lens is similar to the retro-focus Ernostar, which slightly distinguishes it from the Mir and Flektogon series of Planar derivatives.
Of course, this affects the picture of the lens.
ISCO-Gottingen Westron 35 / 2.8 does not shine with high sharpness from an open aperture, on the contrary - on an open aperture, strong vignetting, chromatism (purple halos and borders on objects at the edge of the frame), soft, drop in resolution to the edge (coma) appear. Even the Soviet Mir-1 of Zagorsk OMZ gives a much better picture (according to the joint test). However, it is a bunch of aberrations that form an unusual picture and bokeh, which makes the lens popular (the price in the secondary market reaches $ 100 - not bad for a budget 35?):
ISCO-Gottingen Westron 35 / 2.8. Bokeh lens.
Starting with F / 4, sharpness is aligned in the center of the frame, vignetting is leveled with F / 5.6, and sharpness at the edge of the frame is normalized with F / 8. At F / 5.6-F / 11, the lens copes well with landscapes (but I would like better). You can learn more about the dependence of sharpness on aperture on a more technical resource. here.
The contrast of the lens is quite decent, taking into account the number of glass-air boundaries and single-layer enlightenment. In the backlight, glare and a veil appear, which is corrected in Lightroom.
In other words, the optical quality of the lens is quite sufficient for everyday use, the lens combines effect on an open aperture with good sharpness on a closed aperture.
Conclusions
ISCO-Gottingen Westron 35 / 2.8 - a wide-angle with interesting optical characteristics. Allows you to achieve tolerable sharpness on closed apertures and artistic effects - on an open. The most important disadvantages are the unsuccessful lens design and generally poor image quality - the lens is optically very inferior even to Mir-1.
Thank you for attention. Eshmakov Rodion.
You will find more reviews from readers of Radozhiva here.
Funny. Toxic Lame
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Well, you compared it somehow not quite well with Mir-1. In our Soviet lens, sharpness shows itself well even on an open aperture, and if you cover up to 5, 6 then a razor in general. But if you compare with Mir-1B, then the comparison is just in time.
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Taki Mir-1B is a heavily crumbled Mir-1 ... So everything is correct.
Westron is pretty little in the picture, but you won’t be full of one bokekha.
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The lens, by the way, decided to sell it all the same. It turned out that I needed Pentacon 29 / 2.8.
Who is interested - contact: rudzil@yandex.ru
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Nothing so objective lens, interesting. But World 1 is much better than is commonly believed, I have no complaints about it and in some ways it is better than Helios of 44 modifications.
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Yeah, the picture is not ice, his brother is prettier
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handsome straight .. probably in an all-metal version is it no longer a "state employee" in the picture?
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weak lens, worse than V-shek will be
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There is also Revunon with a similar picture and similar flaws. Most likely, another ideological successor of this scheme ...
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"The optical design of the lens is similar to the retro-focus Ernostar, which makes it somewhat different from the series of Mir and Flectogon lenses - Planar derivatives."
Please tell me, Rodion, how long has THIS been derived from Planar? Both Mir-1 and its ancestor Flektogon are retrofocus lenses. This time.
And secondly, FleKtogon is written through K, not through C.
In general, study, study, study (s)
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Well, about the K in the word Flektogon - yes, I was wrong.
And what about the derivative of which it is - to learn, learn and learn more to you, dear.
Obviously, the presence of a negative meniscus does not negate the fact that the lens is mainly divided into two distinct Gausses in the diagram. Those. we have a negative front lens + banal Gaussian double. In view of this double-Gauss, we can say that this is something five-lens planar-like.
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But the Frenchman himself is your ancestor.
https://en.wikipedia.org/wiki/Ang%C3%A9nieux_retrofocus
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From this Engenie in the Worlds and Flectogons only the front lens itself, which provides the lengthening of the back distance, makes the lens thereby retrofocal - i.e. with a posterior segment more FR.
A very bad sign for classification is the presence of this lens, very, very bad.
So, I'm afraid you are a little wrong.
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I'm afraid, monsieur, that any reference book calls such lenses retrofocus. And you, monsieur, opposed retrofocus lenses to them in your “review”, and even called them the descendants of a symmetrical lens. And who is wrong here?
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Do you think that what is after the front lens in the refofocus lens is pushed “randomly”, without regard to the existing schematic diagrams?
And look at Primagon and Triplet, at Planar (or Biometar, whatever you like) and Mir, at Unar / Ernostar and Kurtagon ... Do you find anything interesting?) Well, that is a pity. They say analogy is a great thing. The engineers were clearly in the know then.
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Any optical design is a development of simpler ones. From scratch, nothing arises. But this does not mean that Tessar should be called a modified triplet.
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This is partly true, because historically the Tessar was blinded from Unar and Protar. Which, in general, does not prevent us from considering it as a continuation of the Triplet idea.
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And, yes, how long has Ernostar become “retrofocus”? Besides you, has anyone called him that over the past century?
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How long have I called him that? We took Ernostar, added a front negative component. And voila - we made the lens based on it retrofocusable.
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Well, that is, do you have your own terminology that has nothing to do with optics? I am happy for you.
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Not, I'm afraid you have problems with the perception of the existing. Perhaps this is somehow connected with the sofa and access to the Internet.
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By the way, planars are not 5-lens ones. Again deuce.
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It’s a pity that there is no smiley facespal on Radozhiv.
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Not a word so sorry.
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By the way, Tronnier proved the possibility of designing a regular Planar with a negative concave front component. So Ultron was born, the same ...
Here - the same case - a Planar with a negative component in front, albeit convex-concave.
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This lens, monsieur, has nothing to do with Planar. From the word at all. Have you ever seen a Planar diagram once?
You are generally aware that a retrofocus lens is an inverted telephoto lens with an extended back section. And the ancestor of all retrofocus is Eugene, from whom they took the name.
https://ru.wikipedia.org/wiki/%D0%9C%D0%B8%D1%80_(%D0%BE%D0%B1%D1%8A%D0%B5%D0%BA%D1%82%D0%B8%D0%B2)
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"Eugene") Go on, go on ...
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Well done, let's continue as you finish school.
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Oh how I waited! I was waiting for this moment!
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Please, only without insults. Talk to yourself, but do not consume too much.
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This phrase is a criterion for the clarity of mind, the lightness of knowledge and wisdom of an older comrade, who certainly knows best of all how, where and how to direct the young generation.
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So in vain you, Arkady, stop this honorable gentleman.
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The moderator is always right. While Rei is on vacation, I'm for her :)
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I apologize if I was harsh in my words. You just have to read very marvelous discoveries here. I understand the review of the lens. There is a diagram - great, no - describe the picture from the lens, its ergonomics, etc. But here is a completely ridiculous theorizing, not supported by anything.
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Everything is written for a simple audience, without unnecessary theory. Yes, something is inaccurate, something is pulled up by the ears. But it is necessary - it helps to understand what to expect from this lens.
Mir-1, for example, gives a very helios-like picture (just look at its bokeh - it is no different in principle). For the scheme is fundamentally similar to Helios (if you forget about the front lens for a minute), which was what we were talking about.
But Westron is a relative of Unar / Ernostar, his picture will be fundamentally different, similar to his "progenitors", despite the same retrofocus scheme.
And after all, this is actually predicted and works. Using one sketch of the circuit, you can understand how the lens behaves.
The analogy is wonderful! She works and helps a lot. Unlike knowing why Tessar really happened there and where the first retrofocus lenses came from ...
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Okay, Rodion, why argue ... We just think in different categories. Perhaps, somewhere they did not understand each other. My advice to avoid such misunderstandings is to avoid using the term "retrofocus" in such a context. Yet the term has a specific meaning associated with a specific progenitor lens. If you said that the lens is a reversed ernostar, or a modified ernostar, it would be clearer and there would not be our long wrangling. I think we just did not understand each other's thoughts.
As for the comparison of Flektogon with Helios, there are certain analogies, of course, since part of the scheme is repeated. Ready to confirm with a picture from Flektogon 2.8 / 35. Still, the lens is noticeably more interesting than the above presented German. There is a little software, but still sharper, and almost does not chromate.
Good evening to you =)
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There are people who can’t share anything practical, but are always in a hurry to demonstrate their superiority over others. It is always so sweet.
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"Or modified ernostar"
This is what was meant.
"Still, the lens is noticeably more interesting than the above presented German."
At some point, the flektogons and helios were tired of - I wanted to try something completely different. Well, here's the Westron. True, I bought it almost immediately along with Pentacon 29 / 2.8, which turned out to be more useful to me because of the short FR.
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“This lens, monsieur, has nothing to do with Planard. From the word at all. Have you ever seen the Planar scheme? "
Have you seen a Jupiter-3 type Zonnar? Want to tell a secret? His dad - Triplet ... And it would seem - where is the triplet?
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Not ... Daddy all and all flat glass with marriage ...
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People, and what do you think is the ideal budget shirik for crop?
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For what denomination? Manual or car? Wide or super wide?
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A manual, perhaps an over-wide but not a fisheye lens, so that you can take photos of landscapes or cities without much distortion of the picture.
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Samyang 14 / 2.8) Navrostrost to FF.
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Among shoemakers, the 28 / 2.8 native autofocus is popular.
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Narrowly on the crop. I use 20 / 2.8 on FF. On crop, IMHO, the most that (soap corners will be cut off).
But Arkady is right, we need even wider type 12-24 :)
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tokina 12-24 used
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Thank you, take a closer look. But in advertisements from 4 three under Canon.
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Rodion, I like your style. good luck!
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a question to Rodion: could you not have removed an even more gloomy “G” for discussing Westron? Well, it was necessary to try so hard - yes, in such pictures any glass will simply behave disgustingly ... never thought about it?
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The author of the review barely finished school - what kind of thought processes can we talk about?
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And you have only one step from love and hate, however) You had only to disagree once, and from Toropov you switched to me ...
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