MS Rubinar 2/100 (LZOS, 1992). Review of a prototype telephoto lens by Rodion Eshmakov

Material on this lens especially for Radozhiva prepared Rodion Eshmakov.

View MS Rubinar 2/100.

View MS Rubinar 2/100. increase.

The name "Rubinar" is strongly associated with reflex lenses, which are based on the developments of the world-famous Soviet optics Dmitry Maksutov. However, in the era of Perestroika and in the 90s, there were lot varied optical creative. At that time, a new, more competitive optics could have been born than the Soviet kondo, but this did not happen - many factories did not survive the 90s and zero at all. However, echoes of those times can still be found today in the form of rare prototypes and limited-edition lenses, which have settled mainly in the hands of collectors and museums. One of these "exhibits" is a non-serial prototype of the fast telephoto lens MC Rubinar 2/100, assembled at the Lytkarino Optical Glass Plant (LZOS). The number indicated on the lens - "92007", indicates that the lens was produced in 1992, apparently this is the seventh copy. Other lenses, however, have not survived, and there is no mention of this lens on the Web. This extremely rare copy was handed over to me for study by representatives of JSC "LZOS".

Specifications:

Optical design - 5 lenses in 5 groups, similar to Biometar / Vega lenses;

Drawing of the optical scheme of the Rubinar 100/2 lens from the documentation.

Drawing of the optical scheme of the Rubinar 100/2 lens from the documentation.

Focal length - 100 mm;
Relative aperture - 1: 2;
Aperture - 15 matte blackened blades, without preset mechanism;
Aperture limits - F / 2 - F / 16;
Frame format - 36×24 mm (calculated), 44×33 mm (covered);
The minimum focusing distance is 1.2 m;
Mounting thread to the camera - M42;
Others - non-standard thread for filters, multilayer coating of optics.

Lens Design Features

The Rubinar 2/100 uses a layout typical of LZOS optics, with an aperture control ring on the lens nose and a convenient wide focus ring. The lens is very compact - slightly larger than the old-old Jupiter 9, and noticeably less "cropped" fifty dollars Zenitar-S 50/1.2sdeveloped V. Bogdankov right now, in 2016. The design of the helicoid is the same as that of Industar-61 L / Z. The focuser provides an MDF of 1.2 m - for this focal length, this provides a 1:10 image scale, which is rather mediocre.

The diaphragm is controlled by a steplessly rotating ring. There is no preset mechanism. It is especially “funny” that there is also no mark on the case for setting the aperture.

There is no mark on the lens indicating the set aperture value.

There is no mark on the lens indicating the set aperture value.

The aperture itself of the Rubinar 100/2 has 15 rounded petals, in appearance and size it is very similar to the aperture of the Lytkar lens Jupiter 9.

Aperture Rubinar 2/100.

Aperture Rubinar 2/100.

Most likely, this copy was not at all intended for demonstration to the general public and was a kind of layout in the style of "I blinded you from what was." This is also supported by the quality of the assembly of the lens block of the lens: on the lenses there are scratches of enlightenment, chips, exfoliation of blackening - defects that are completely unacceptable for a product that claims to be a series.

Moreover, even the seemingly beautiful "ruby" multilayer coating turned out to be very doubtful in its properties. Measurements of the optical transmission spectrum made it possible to establish that the light transmission coefficient of the lens in the wavelength range from 400 to 760 nm is 85%, but if we take the widest limits of the visible range - 380-800 nm - we will get only 81%. Although (post) Soviet optics In the 80s and 90s, the quality of enlightenment was generally not famous, this lens also demonstrated a complex uneven light transmission profile with a maximum in the orange region.

The light transmission spectrum of the Rubinar 2/100 lens prototype in the range of 300 (UV) -1100 (IR) nm.

The light transmission spectrum of the Rubinar 2/100 lens prototype in the range of 300 (UV) -1100 (IR) nm.

The situation with the transmission profile is even worse than another prototype of the same era - Belar-2 90/2.5. A complex non-linear profile introduces hard-to-correct image color defects that prevent the camera from properly positioning white balance and make it difficult to color correct in post-processing. Often even with primitive single-layer enlightenment the result is more predictable.

Below are more photos of the appearance of the Rubinar 100/2 prototype.

The appearance of the lens gives the impression of a very raw product, not ready for production. In fact, it is so, but even in this form it is suitable for evaluating its capabilities as a photographic lens.

Optical properties

Note that Rubinar 100/2 uses a very old and simple five-lens optical design. It's very funny that the exact same one is used by the one released 10 years earlier Nikon Nikkor 105mm 1: 1.8 (AI-S) – looks like copying Nikon optics in Russia older tradition than I thought. In general, Rubinar 1992/100, produced in 2, was already outdated by at least 10 years, especially since in 1991 the world already saw autofocus Canon EF 100 / 2 USM with a new eight-lens scheme.

However, due to the correction of spherical and, in particular, chromatic aberrations in the center of the frame, the Rubinar 100/2 provides good sharpness from an open aperture - much better than, for example, projection lenses 35KP-1,8 / 100 or PO501-1. Along the edge of the frame at equal apertures, the lens is inferior to those close in parameters Uran-27 100/2.5 и Belar-2 90/2.5 due to a higher level of coma. You can also note a higher level of vignetting in Rubinar 100/2 in comparison with these lenses. Despite this, it covers 44x33mm and larger without difficulty, which allowed me to use it with a shift adapter on a full-frame camera. Outside the 36x24mm frame, the lens has noticeable pincushion distortion, which is typical of small format lenses with a circuit Biometar/Vega.

The contrast of the formed image, even under normal conditions, is rather mediocre - the low quality of the blackening of the lenses affects. It didn’t work out to fix it - they are rolled into aluminum frames. In backlight, Rubinar 100/2 works very poorly due to strong white veiling. The color reproduction is distorted, often with the presence of a hard-to-correct parasitic green tint. In terms of contrast and color reproduction, the Rubinar 100/2 prototype disappointed me greatly, especially when compared with the brighter and richer photographs that I received with Belar-2 90/2.5.

I was pleased with the unobtrusive, but recognizable "Planar" bokeh in the lens, which reminds me of the blur of another lens with a similar scheme - Vega-M-1 35/2.8. The coma level of the Rubinar 100/2 is much lower than that of lenses like Helios-44 or Helios-40, and spherical and chromatic aberration not as pronounced as in the projection PO501-1 , so the blurring of the background does not tend to distracting "rattling" unevenness and color distortion by chromatism.

The following are sample photos taken with the Sony A7s full frame camera.

The following are panoramic photographs taken on a Sony A7s using a Fotodiox EOS/NEX shift adapter ("shift mounts"), which provides a frame format of "36x45" and "24x56" mm - which is larger than a 44x33 mm frame Fuji GFX medium format cameras.

Conclusions

Apparently, optically Rubinar 100/2 is quite good for a post-Soviet lens of the 90s, although the performance of a particular instance leaves much to be desired, in particular, the choice of anti-reflective coating and assembly of the lens block. Already at the time of development, the Rubinar 100/2 was hopelessly outdated - that was the era of productive multi-lens autofocus lenses with an electromagnetic diaphragm for large black SLRs. But, paradoxically, today the outdated optical design, with all its shortcomings, makes the Rubinar 100/2 even more viable product than in 1992, since today there is a demand for "creative lenses" in addition to productive solutions. And there was and is an understanding of this at the enterprise.

You will find more reviews from readers of Radozhiva here... All Rodion reviews in one place here.

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Comments: 17, on the topic: MS Rubinar 2/100 (LZOS, 1992). Overview of a prototype telephoto lens by Rodion Eshmakov

  • Albert

    Yongnuo 100/2 with autofocus and multi-bladed aperture can be found for 150 bucks.
    Even if they release 100/2 now, it will cost 600 bucks and will be as primitive as this prototype

    • Rodion Eshmakov

      There is no reception against Yong, it's true) So this lens today is like the Zenitar 85 / 1.4, which appeared after the cheap Samyang. On the other hand, the same Nikkor 105 / 1.8 is very expensive in the secondary market. If this lens in its normal version had a price close to the yong, then it could get a certain audience.

  • Sergei

    I would like the author to still voice the “non-standard” thread size for filters and the weight of this subject.
    I was very surprised by the weak MDF and the light transmission of this lens.

    • Rodion Eshmakov

      OK, ~57 mm. 58 does not climb, 55 is not enough. Mass did not measure, not interesting.
      Light transmission is not weak, it is at the level of other similar lenses. Belar-2 is not much better - 0.83. 35KP-1,8 / 85 LOMO 1991 with MS - 0.85.
      MS Helios-44M-4 - 0.8. I-26m - 0.85. 7Artisance 50 1.1 – 0.83. These are the data of my measurements for the same wavelength range - 380-800 nm.

      • Sergei

        Complaints about light transmission relate to its uniformity in the entire visible range, and not to the overall coefficient.
        Moreover, the requirements for a shooting lens are usually higher than for a projection lens.

        • Rodion

          Ah, so the light transmission profile of such a curve actually has many lenses with MS from the last century. In (post) Soviet optics, it is, of course, more crooked than in Japanese and German, but not always. This is the trouble of the old MS with 2-3 layers and incomprehensible initial TK. There will be an article on enlightenment and spectra, but I don’t know when - this is difficult material to present.

          • Sergei

            I think that here the merit of the old brands of optical glass is more than the enlightenment, unfinished by optics designers.

            • Rodion Eshmakov

              No, glass in general is hardly very different from what it is now. At least in this particular lens there is definitely no TBF-10.
              Glass affects, but only transmission in the region of 300-400 nm. Lead failure in this area is normal. There, in general, for many oxides, the absorption band corresponding to charge transfer lies. Everything else that just affects the white balance and color reproduction is precisely enlightenment. In this lens, most likely, a two-layer is used - the transmission profile can be mentally decomposed into two “buckets” (see the view of the transmission profile for single-layer coating in the review 16KP 65 / 1.4). The problem is that the transmission peaks of the layers are too far away, which is why such a sharp transition is obtained. In some lenses, the layers, on the contrary, differ too little in their properties from each other, because enlightenment does not work much more efficiently than a single-layer one, but the color does not spoil much either.

  • German10

    Rodion, thanks for the review! It can be seen how passionate you are about this topic - every time I am surprised and admired!

  • mr.swar

    This is a typical prototype from the Central Design Bureau or SKTB, which worked out the salary and the lens could be exhibited at the VDNKh exhibition, showing the success of the superpower.
    It makes no sense to demand diffraction quality from this specimen, it has not been finished. For good, they had to make 3-5 lenses and finish them. Yours is apparently molded from what they did or the remains of other copies. Look for the people who created this lens and they will share information with you.
    PO Arsenal tore mostly Nikon.
    LZOS could rip off from Pentax or Olympus, sometimes from the Germans.
    By and large, look for people who will tell the story of this lens and you tell us.

    This is the trouble of the old MS with 2-3 layers and incomprehensible initial TK.
    “The specification is compiled on the basis of the film color material used, as it was in the 70-80s. This can be a different color material - USSR (Shostka and Kazan), GDR (rare), Agfavsky, Kodakovsky, Fujivsky, etc. 2-3 layers of MS are optimal for optics of the USSR of the period from the end of the 70s to the end of the 80s”

    Glass affects, but only transmission in the region of 300-400 nm. Lead failure in this area is normal. There, in general, for many oxides, the absorption band corresponding to charge transfer lies. Everything else that just affects the white balance and color reproduction is precisely enlightenment. In this lens, most likely, a two-layer is used - the transmission profile can be mentally decomposed into two “buckets” (see the view of the transmission profile for single-layer coating in the review 16KP 65 / 1.4). The problem is that the transmission peaks of the layers are too far away, which is why such a sharp transition is obtained. In some lenses, the layers, on the contrary, differ too little in their properties from each other, because enlightenment does not work much more efficiently than a single-layer one, but the color does not spoil much either.
    “To make an accurate white balance for a photographic lens of the 70-80-90s period did not make any sense. We return to the fact that film color materials had different color rendering curves, so it is easier to make the necessary color correction for a certain film color material. You just haven't worked with Kodak and don't know many things. You can not play with the number of layers, they are played with different anti-reflective material and on different glass. Applying an extra layer of coating on the lenses, the technologist will not miss, therefore, lenses different by year of production had a different reflex on the lenses, both outside and inside”

  • Sergei

    In my opinion, this Rubinar 100 mm / 2 is just an attempt by LZOS in the early 90s to create a successor to the obsolete Jupiter-9 (seven lenses in three components - two triple gluing!).
    And with minimal overhead. Hence, there are five lenses in the optical scheme (even Nikon, with a similar number of lenses in the famous 100 / 2,5, did not dare to increase the aperture ratio).
    As a result, it was not possible to achieve a stable and high-quality drawing even according to the criteria of the 90s. The cost price of the novelty turned out to be much higher than the honored veteran Jupiter-9.
    But he still had the niche of retro optics and the charm of the classic Zonnar scheme.
    The outward failure of LZOS is an attempt to extend its universal proprietary brand Rubinar to a conventional optical lens scheme, which caused confusion and unnecessary associations.

    • Rodion

      The fact that, most likely, it was a replacement for Jupiter-9 - I agree. These patches in his scheme still cause LZOS engineers to burn below the back. For them, in general, the mention of Jupiter-9 is very unloved - there were many problems with it, and we ourselves see this by the quality (missing) of Jupiter-9 lenses produced by LZOS.
      I do not agree that Nikon did not risk something there. In this article, I mentioned the Nikkor 105 / 1.8, made according to this scheme. That is, Nikon not only “took a chance” and made f / 1.8 in five lenses, but they also achieved good performance, moreover. Most likely, at LZOS they decided to repeat their experience in this lens.
      Further, the cost of this lens would definitely be lower than that of the Jupiter-9. The only problem was the time in which this lens was developed. Before the era of affordable digital SLRs, no one thought about “charm”.
      I support the opinion that spreading the Rubinar brand, by analogy with Zenitar, to all LZOS optics is a failed idea. I think that only catadioptric lenses should be called this way.

  • mr.swar

    There was an error in the penultimate comment. Instead of LZOS, read KMZ.

    Still, my assumption was torn from the Pentax-M 100 / 2.8 or Nikkor 105 / 1.8 lens.
    Removing the performance characteristics of Pentax-M 100 / 2.8, I received the following results:
    2.8 - 60 lines center and edge.
    4.0 - 70 center lines and 60 edge lines.
    5.6-8.0 - 80 center lines and 70 edge lines
    In fact (reference copy) Rubinar 100 / 2.0 should have had similar characteristics. Try to remove the characteristics.

    Telear-N 200 / 3.5 torn apart with Nikkor 200 / 4.0

    Kaleinar-5N 100 / 2.8 is very similar to the optical schemes of the late 70s and early 80s and had very good characteristics in the region of 60 center lines and 50 edge lines.

    Arsenal and KMZ have been competing since the mid-to-late 60s. The appearance of Kyiv-10 added fuel to the fire between the design bureau and the factories even more.
    Arsenal chose the Nikon mount for 35 mm film, and tore all the optics from Nikon.
    KMZ chose the K mount for 35 mm film, and presumably ripped it off Pentax, looking at the others.
    In the late 80s - early 90s, Arsenal had Kyiv-19, Kyiv-20 and prototypes that did not see mass production.
    Kyiv-19 and Kyiv-20 were a great success, so KMZ did not stand aside and Zenit-AM / AM2, APK models appeared, which clearly needed a new portrait and telephoto lens.
    Kyiv had Kaleinar-5N and Telear-N, as well as ZUM Granit-11, blocked the focal lengths with a margin.
    Zenit-AM and AM2, apart from Tair-11K and Jupiter-37K, had nothing, with the exception of the Telezenitars and Oberons, which were expensive to manufacture. Presumably, from the mid-80s it was necessary to create prototypes of 100-200-300 mm lenses for Zenit-AM / AM2, APK cameras, so that they could compete with Kyiv-19 and Kyiv-20. Perhaps Rubinar 100/2.0 was this prototype. The collapse of the USSR further threw off cooperation and economic ties between countries, and by the mid-late 90s, cameras with lenses were not needed in domestic markets. Foreign markets were closed, as there were no representatives, service centers, etc.
    Here is such a sad story of Arsenal and KMZ.

  • mr.swar

    UPDATE.
    Close cooperation and cooperation between KMZ-LZOS.
    Close cooperation and cooperation of GOI-ZOMZ.
    Draw conclusions.

  • Sergei

    A little away from Rubinar.
    Concerns the opinion of advanced lovers of apochromatic optics about LZOS products.
    Lots of learning.
    https://whale-roma.livejournal.com/281191.html

  • mr.swar

    Sergey, regarding your link.
    This information is so outdated that it can be thrown out and forgotten.
    All lens blocks date back to the beginning of 2000-2005.
    Who ate LZOSovsky shit in the period 1995-2012 will never work with them again. Now and even more so, they are foreign economic corpses, only the local market.
    Google how they sued the manufacturer of ceramic elements for crucibles and what it cost them. Specific ceramic elements with a high content of rare earth materials are made to order and only under LZOS. These are not some ordinary platinum crucibles, which, like dirt, ceramic elements partially dissolve in OK grade glass, so there is a limit on the number of melts. Glass of OK brands is considered aggressive optical glass, and in order to obtain normal homogenization and clarification rates, it is necessary to tear the Russian navel, and not how it turns out after melting, and still compete with Ohara, Hikari, Shott in the world market, but this is already in the past.
    When smelting glass grades OK, the yield of usable glass is 30-40%, everything else is a waste.
    I myself fell for their bait, but before ordering I received a sampler and it was defective in some respects.
    It is easier and more reliable to work with the Chinese and Japanese, proven guys and without setups.

    Professor Preobrazhensky very rightly remarked: "And - God save you - do not read Soviet newspapers before dinner." To this Dr. Bormental replied that there were no others besides them. To which the professor objected: “Don’t read any of them.

  • Sergei

    Back in 2008-2012, LZOS ended the last program for the production of astronomical glass-ceramic mirrors, and no more orders were received. This material has a very low coefficient of thermal expansion and a short thermal stabilization time.
    But the sitall is outdated, and is inferior to its analog from Schott - Zerodur in quality.
    The latest innovations - the American space super-telescopes Hubble and Webb were made from fundamentally different materials.

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