Cyclop 1,5 / 85 (ROMZ) - a technical version of Helios-40-2 for use in night vision devices, adapted with an iris diaphragm. Review from Rodion Eshmakov

Review of the Cyclop 1,5 / 85 lens specially for Radozhiva, prepared Rodion Eshmakov (subscribe to Instagram!).

The eye of this Cyclops got an iris.

The eye of this Cyclops got an iris. increase.

I haven't heard about Helios-40, probably only those who have never taken a camera in their hands. This lens is, perhaps, one of the most popular in the 85 / 1.4 class, as well as - in fact, the only consumer photographic lens of this kind produced in the USSR. Despite this fact, Helios-40 still costs a lot of money in the secondary market, as a rule, more expensive than more modern manual counterparts. The reason for this is its "legendary character", due to a rather specific picture and, of course, skillful PR. In the CIS, it was the attempts to obtain a cheap "analogue" of Helios-40 that led to the attention to projection, technical and cinematographic lenses; accumulation of knowledge and skills in the field of adaptation and modification of technical optics. Therefore, "heliosophy" can be regarded as a rather useful phenomenon.

The calculation of Helios-40 was made by D.S. Volosov (also known as the author of the book "Photographic Optics") in 1950, obviously with an eye to Carl Zeiss Jena Biotar 75 / 1.5 (1938). The reason why the original lens was not recalculated keeping the basic parameters (like other German ones - Biotar 58/2, Sonnars 135/4, 50/2, 50 / 1.5, 85/2, Biogon 35 / 2.8) is not clear. There are many speculations on this basis, but the most logical and obvious option - they could not do it differently. The palette of optical glass in the post-war USSR was extremely poor, all problems had to be solved purely by the geometry of the lenses, and hardly efficiently: the lens was produced (and is being produced now) at the KMZ, where even today there are restrictions on the manufacturability of the production of lens components (you can read about this in my note on the products of the current KMZ). One way or another, but Helios-40 turned out to be 10 mm longer than its progenitor, heavier and, generally speaking, noticeably differs from it in optical properties.

Helios-40 has been mass-produced since the beginning of the 50s in several versions [Source]:

  1. Helios-40 F = 8,5 cm 1: 1.5 P, Contax / Kiev, non-serial prototype of GOI;
  2. Helios-40 F = 8,5 cm 1: 1.5 P, M39 mount for SLR cameras, unpainted aluminum case, anti-reflective violet and blue shades, CMZ;
  3. Helios-40T, TV version for taking pictures from a fluorescent screen, in a special frame, amber coating, KMZ;
  4. Helios-40-2 1,5/85, M42 mount for SLR cameras, black body, amber coating, tripod foot, KMZ (from the late 60s to 1990);
  5. Cyclop 1,5 / 85, M42 mount for SLR cameras, lightweight simplified body without diaphragm, amber coating, ROMZ (1990-1994) (presented in this article);
  6. Helios-40-2 1,5 / 85, M42 mount for SLR cameras / Canon EF / Nikon F, black body, double-layer coating, without a tripod foot, KMZ (since 2012);
  7. Helios-40-2 1,5 / 85, M42 mount for SLR cameras / Canon EF / Nikon F, black body in a new design, double-layer coating, without a tripod foot, KMZ (since 2014).
  8. Meyer Optik Görlitz Somnium 1: 1.5 / 85mm (2015) - rebranded and repainted Helios-40-2 arr. 2012.

Since in the late USSR there was no great demand for this product, in 1990 Helios-40-2 was transferred to the Rostov OMZ for production in the version for the night vision device (EOP1 generation) NZT-1. The new lens received the name "Cyclops" (apparently, due to the absence of an iris diaphragm - the children of Uranus did not close their eyes) and the body was redesigned to make it as cheap and lighter as possible. The optics, most likely, were still manufactured at the KMZ without any visible changes relative to the Helios-40-2 optics. Lenses were produced about several thousand copies, after which ROMZ designed a highly specialized IR lens with the same parameters, but completely different scheme.

This article is about a modified Cyclop 1,5 / 85 lens with an internal iris installed.

Specifications [source: 1, 2]:
Optical design - Biotar / Helios, 6 lenses in 4 groups;

Basic optical scheme of Helios-40.

Basic optical scheme of Helios-40.

Focal length - 85 mm;
Aperture ratio - 1: 1.5;
Field of view - 28 °;
Coverage circle - ~ 53 mm;
Frame format - 36 * 24 mm;
Rear focal distance - 44.5 mm;
Filters thread - 67 mm;
Weight - 450 g;
Camera attachment thread - М42;
Features: does not have an adjustable aperture.

Lens construction and adaptation

Cyclops uses a body that is simplified and lightweight compared to a photographic lens design: the mass of this version of the lens is half that of a conventional Helios-40-2. On the title ring - the name in Latin letters, parameters, the ROMZ emblem and the serial number, indicating the release of the lens in 1993. Interestingly, the lens can be easily mounted on modern cameras thanks to the M1 threaded mount with a standard flange used in the NZT-42 monocular.

However, the Cyclops does not have an iris diaphragm, and without one it is quite difficult to use the old 85 / 1.5 lens. There is very little space in the lens to set the aperture. I had to resort to the help of a turner to prepare the bore diameter for a diaphragm with the required hole diameter - 37 mm. Its thickness was slightly larger than necessary, as a result of which the front and rear lens units were moved apart by ~ 1 mm. Strictly speaking, this is not critical for planar lenses. Objectives with FR 85-100 mm “tolerate” a change in the distance between the lens units by ~ 3-5 mm without noticeable changes, and it is usually more harmful to bring the lens units closer together.

Unlike the factory version with a XNUMX-blade diaphragm with an irregular star-shaped aperture, this lens features an eighteen-blade perfectly round iris.

View of a multi-leaf iris diaphragm installed inside the lens.

View of a multi-leaf iris diaphragm installed inside the lens.

The control of the diaphragm was brought out to a decorative body ring on the thread, by chance it appeared in the right place.

Cyclops from the shank side. The ring and leash of the diaphragm control are visible.

Cyclops from the shank side. The ring and leash of the diaphragm control are visible.

The focusing mechanism of the lens is greatly simplified in comparison with the Helios-40-2: a multi-start thread is cut directly onto the lens unit, when focusing, the lens unit rotates entirely, which complicates the use of polarizing filters. But you can achieve a very small MDF (about 0.5 m) by unscrewing the helicoid stoppers. The movement of the helicoid is soft and easy - focusing is pleasant and comfortable.

Cyclops when focusing at infinity.

Cyclops when focusing at infinity.

Maximum extension of the lens unit of the objective when focusing on the MDF.

Maximum extension of the lens unit of the objective when focusing on the MDF.

Interestingly, the lens retains a movable tripod foot, which can be useful when using a tripod due to the large mass of the front lenses.
Cyclops lenses use a single-layer amber-hue, typical for late Soviet optics. In the light, the lens, however, still slightly yellows.

View of the entrance pupil of the Cyclops with a closed diaphragm.

View of the entrance pupil of the Cyclops with a closed diaphragm.

I never liked the original Helios-40 precisely because of its design: it is too heavy and uncomfortable, and the “circular saw” of the diaphragm also disturbs, which greatly spoils the bokeh during diaphragm control. The adapted technical lens of the NZT-1 night monocular Cyclops turned out to be devoid of the critical shortcomings of its shooting brother: it is lighter, it is more compact, it is more convenient, it has the correct aperture. But such alteration may not be available to everyone due to the need for turning work.

Optical properties

The Helios 40 was definitely never meant to be a high quality lens. Everything in it betrays a compromise approach: this is the use of the old optical scheme, and the increase in focal length in comparison with the CZJ Biotar 75 / 1.5, and the use of deliberately thickened lenses, and mediocre resolution with a pronounced dip in the thirds of the field.

The graph of the resolution distribution over the Helios-40 field.

The graph of the resolution distribution over the Helios-40 field.

This is not surprising, considering that Helios-40 uses common types of glass available in the world back in the 30s: the most important "high-tech" in Helios-40 is barite flints with a refractive index of 1.64 (for comparison: highly refractive is called glass with a refractive index of about 1.8).

Card Helios-40 in the GOI catalog.

Card Helios-40 in the GOI catalog.

By the way - about glass: it is surprising that of the types of glass required for the production of Helios-40 in the Russian Federation, only LF-5 and TF-1 are produced at the LZOS plant, but Helios-40-2 lenses have been produced at KMZ for almost 9 years. Draw your own conclusions.

Cyclops, however, was made from ready-made lenses Helios-40-2, therefore, it is optically identical from it without reservations.

At open aperture, lens sharpness is mediocre due to highly pronounced spherical aberrations and chromatism. Something terrible is happening across the field, but in accordance with the above schedule: Cyclops completely rejects the traditional composition - the "rule of thirds". The resolution is limited by the field aberrations rather than by the field curvature. The situation is corrected with aperture to f / 2 - with a multi-blade diaphragm of the correct shape, this can be done completely without a twinge of conscience. At F / 2 and beyond, the Cyclops is a good, sharp lens in the center of the frame. Field aberrations can be corrected by aperture down to ~ F / 8. In terms of optical quality, Cyclops is much inferior to projection lenses at equal apertures, especially in field. In the center, the difference is not so significant.

The contrast in Cyclops is not very important even under normal shooting conditions, but in backlight it is quite bad: the lens "fades" in the sun due to strong veiling, and catches iridescent lens flares. Photos require editing in the editor (levels will no longer help, you need to use curves).

It is worth noting one remarkable property of Cyclops-Helios: its real coverage circle is more than 50 mm, which allows it to be used on mirrorless full-frame cameras with a shift adapter to increase the angle of the field of view. This is the first time I used a mirror lens Rubinar 300 / 4.5... The use of the shift adapter allows you to fully use the second (edge) maximum resolution of the lens and bypass problems with framing. At the same time, we get an increase in the size of the picture: with vertical panning, the maximum attainable physical size of the image is 48 * 36 mm, Cyclops with a frame of this size becomes the equivalent of a full-frame 60 / 1.1 lens on a 36 * 24 mm matrix.

Comparison of the field of the image, available with the shift adapter on a full-frame camera, with the field of the usual frame 36 * 24 mm.

Comparison of the field of the image, available with the shift adapter on a full-frame camera, with the field of the usual frame 36 * 24 mm.

In fact, when shooting handheld due to shaking, you have to resort to some cropping, as a result of which frames are obtained with a resolution of ~ 20 Mp (instead of 24 Mp ideally) with an aspect ratio of 4: 5 (conventionally "45 * 36 mm") at vertical panning. The frame 45 * 36 mm, by the way, is larger than that of medium format Fujifilm G cameras (44 * 33 mm).

The use of a shift adapter allows you to very well realize what Helios-40 is usually loved for (or vice versa): a specific expressive bokeh. Due to the pronounced spherical aberration, the discs of confusion acquire a bright edging, and strong vignetting and coma give the discs at the edge of the field the appearance of "lemon" with a bright edge oriented towards the center of the frame. The doubling of the physical size of the frame allows you to “enjoy” the work of field aberrations and vignetting to a greater extent. Aperture down to f / 2 simplifies bokeh a little, making it a little less intrusive. Since this aperture also significantly improves the overall image quality, using a lens at f / 2 seems like a very good idea. It's good that the diaphragm is round :).

Cyclops proved to be excellent with the shift adapter: I liked the bundle so much that in the end I began to shoot more panoramic photos than usual, even despite a number of difficulties in shooting and processing.

Below are sample photos taken with a full-frame Sony A7s, 4: 5 photos taken using the Fotodiox EF-NEX Shift Adapter. A number of photographs were taken using a polarizing filter.

Conclusions

The adapted technical version of Helios-40 for NVG monocular NZT-1 - Cyclops 1.5 / 85 - turned out to be almost more successful in design than the original photo lens. It is lighter, more convenient, and the installed aperture of a perfectly round shape solved the main problem of the original Helios-40 - poor image quality at an open aperture with undesirable aperture due to bokeh distortion. The use of a shift adapter and a round aperture diaphragm on a full-frame camera made it possible to bypass a number of optical sins of the lens while dramatically improving the artistic properties and image quality. Thus, Cyclops (in essence - Helios-40) is a lens with great potential, but very complex and capricious to use, requiring tweaks both in shooting and in processing.

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

Add a comment: Rodion

 

 

Comments: 28, on the topic: Cyclop 1,5 / 85 (ROMZ) - a technical version of Helios-40-2 for use in night vision devices, adapted with an iris diaphragm. Review from Rodion Eshmakov

  • IL-76

    I use such a Cyclops regularly on the Sony A7R3, much more convenient than the usual Helios 40, only I removed the tripod foot from it so that it would not interfere. On the open side, there is enough sharpness, so I use it without aperture. Covering more than a FF frame is a common thing for manuals. To get a picture from the edges, using the Metabones Speedbooster Ultra on a Sony A7R3, it almost does not vignet in the full frame. It turns out a "medium format" picture, a fairly large coverage is provided not only by manuals, but also by many EF lenses. Minus - you always need to crop the photo a little from the black edges, as a result, the crop factor is around 0,78-0,82 - like a “digital” SF. It is also good that the original speedbooster hardly eats up the light - there, according to experience, less than 1/3 of a stop loss.

  • Ivan

    Thanks for your review. I admit I misunderstood something.
    "Of the types of glass required for the production of Helios-40 in the Russian Federation, only LF-5 and TF-1 are produced at the LZOS plant, but Helios-40-2 lenses have been produced at KMZ for almost 9 years."
    How is the modern Helios-40-2 made now?

    • Arkady Shapoval

      apparently it was counted for another glass, but no one will tell us about it. If they say - old lenses will rise in price

  • Alex

    Where did you get the diaphragm? I thought at first that it was from Tair, but there are 20 shiny petals.

    • Rodion

      I bought a microscope

      • mAlex

        Microscopic - from the Biolama condenser?

        • Rodion

          No, but that type, yeah.

          • mAlex

            I want to try to fit one in the G-92 from LETI into the middle of the lens block.

  • Vlad

    I also have an old Cyclops and a brand new Helios 40-2, it's all lies that the G-40 in the open is not sharp, sharp! but he, too, is good in certain cases of his picture-bokeh.

  • Sergei

    Information about Helios-40T is given somewhat incorrectly. This lens was designed to project an image onto a vidicon (ortikon) with dimensions of 24 x 32 mm.
    And not for re-shooting from a fluorescent screen to photographic film.

  • Jea reth

    So I waited.
    It remains only to somehow attach the lens that I was talking about on the BZK. Although I have little idea how this can be done with his RO.

    I remember that I was driving the G-40 in the M39 version. A friend bought it for herself and gave it to me to put it in order, because there the grease died a terrible death from time to time. Well, it's heavy, a dog ... Although on covered up to 2.8 it gave in general sufficient resolution for 13MP on FF. Here is a snapshot from him.

    • Jea reth

      The onion grief does not want to attach

    • Rodion

      The one you spoke about is unrealistic to transplant in its pure form. At least on the A7s for sure. But it's tempting, what can I say.

    • UstasFritZZZ

      Heavy ... After Sigma 85 1.4 Art all other lenses seem light))

      • Arkady Shapoval

        After 105 1.4 Art

        • UstasFritZZZ

          I didn't hold 105 in my hands yet, but after 85 the impression remained for a long time

  • B. R. P.

    Dust-dirt, probably it is hammered into this gap ...

  • Molchanov Yuri

    Great! It was worth the trouble to install the diaphragm. Thanks for your review!
    Gradually I forgot both sites where I used to spend a lot of time (DXOmark and lenstip), but it is impossible to part with radojuva largely thanks to your articles. Thanks again!

  • tryamer

    used Cyclops, Cyrillic inscription. another interesting feature, dear met. lid, with a neat round hole in the center. about 1mm. With hands on ISO 320, on a sunny day, you can shoot. the picture comes out with a low resolution and a huge grip. it is also very useful with film if the sensitivity is around 1-3 units.

  • Jury

    A wonderful review from Rodion of the technical version of the Helios-40-2 lens. By chance, there was such a copy in my hands. The lens upset me with terrible aberrations and significant chromatism. All this did not fit with the responses to this lens by many authors. Fortunately, there is an optical design with all sizes of distances between lenses. He admitted that the lenses were made with high quality (Rodion confirms that these are the products of Krasnogorsk), but the lathe may not correspond to Volosov's calculations. In the end, it turned out that way. When I adjusted all the gaps between the lenses, the result was amazing. After that, he made the necessary adjustments. Added an iris diaphragm from Chinese comrades. I used a helicoid from a Mir26 lens with minor modifications. The weight turned out to be about 770g.

    • Rodion

      And what gaps were not maintained and by how much?

      • Jury

        Good afternoon There are working records in the course of lens adaptation. I can send them to whatsapp.
        The gap between the first and second lens should be 0.07mm, in fact 0.3mm. Between the latter should be 0.2 mm, in fact 0.4 mm. Last size tolerance +\-0.03mm.

        • Rodion

          Hello! Thank you for your reply, please email: rudzil@yandex.ru, or in social networks (VK, FB, Inst)? Also wondering where they found the gaps that should actually be there? Unfortunately, I don't have a G40 scheme.

  • Jury

    Good evening! Concerning the sizes... The sizes are specified on the basic optical scheme in your work. Unfortunately, perhaps this is the only lens for which there is initial information (((.

    • Rodion

      Oh, well, yes) I thought there was some other source)

  • Jury

    Alas, there are no primary sources on lens blocks, they would fit very well (((. This is not enough ... I suspect that the lathe is the source of many troubles.

    • Rodion

      Yes, I still don’t have documentation for this asshole)

      • Jury

        I would like others too :)

Add a comment

Copyright © Radojuva.com. Blog author - Photographer in Kiev Arkady Shapoval. 2009-2023

English-version of this article https://radojuva.com/en/2021/06/cyclop-1-5-85-romz/?replytocom=463029

Versión en español de este artículo https://radojuva.com/es/2021/06/cyclop-1-5-85-romz/?replytocom=463029