35KP-1,8 / 75, adapted with the ability to control vignetting. Review from Rodion Eshmakov

Review of the cinema projection 35KP-1,8 / 75 prepared Rodion Eshmakov (subscribe to Instagram!)

"Classic (or already banal?) 7/5" in a universal design for SLR cameras.

"Classic (or already banal?) 7/5" in a universal design for SLR cameras. increase.


The 35KP-1,8 / 75 cinema projection lens has been produced at the Izyum Instrument-Making Plant (IPZ) since the 1980s. He came to replace the old LOMO J-53 75/2differing from him more aperture and a more advanced optical design. Projection lenses are relatively affordable and are generally viewed by hobbyists and enthusiasts as an alternative to high-aperture portrait lenses.

This article presents the 35KP-1,8 / 75 lens, adapted for use with modern cameras. In addition to the basic conversion procedure (setting the iris diaphragm and the focusing mechanism), the lens received an interesting opportunity to quickly adjust the vignetting level during shooting, this option was also implemented by me for lenses 35KP-1,8 / 100, PO501-1 100/2 and a number medium format optics.

Specifications:

Optical design - 7 lenses in 5 groups (Planar);

scheme 35KP-1,8 / 75Possible optical concept of the lens.
Focal length - 75 mm;
Aperture ratio - 1: 1.8;
Frame format - 16 * 22 mm (calculated), covers the frame up to 44 * 33 mm without strong vignetting;
Landing diameter - 62.5 mm;
Features: projection lens, no iris and no focusing mechanism.

Design and adaptation

By design, the lens is a no-frills aluminum tube lens unit. One slotted nut secures the lenses inside the aluminum pancakes and one lens spacer. LOMO lenses are made in a similar way, but they have slotted nuts on both sides of the body, which facilitates access to the lenses. Lenses 35KP manufactured by MMZ im. Vavilov are less technologically advanced, but durable: their lenses are not rolled into aluminum, i.e. the lens unit design is similar to conventional photographic lenses.

Important! The lens design has an unobvious drawback: apparently, due to poorly selected materials, when the lens was used in the projector, the geometry of the lens mounts was distorted from heating. For this reason, these particular lenses often have wobbly lenses and extremely poor image quality, which is not typical for optics of this technological level. Of the three lenses I purchased, only one had good sharpness, the rest, being outwardly defect-free, had an unsatisfactory image quality. Most likely, the comment applies to other lenses produced by the IPZ.

View of the adapted 35KP-1,8 / 75 from the side of the front lens.

View of the adapted 35KP-1,8 / 75 from the side of the front lens.

Although the 35KP-1,8 / 75 does not have a diaphragm, it is not difficult to install it even using the native lens spacer.

Multi-blade aperture diaphragm installed in 35KP-1,8 / 75.

Multi-blade aperture diaphragm installed in 35KP-1,8 / 75.

The rear section 35KP 75 / 1.8 is enough for trouble-free adaptation to any small-format SLR cameras, and it is so large that it becomes possible to install a second (lens) iris diaphragm in order to implement vignetting control.

View of the double iris diaphragm of the objective through the front lens: the aperture is covered, the lens is closed.

View of the double iris diaphragm of the objective through the front lens: the aperture is covered, the lens is closed.

Old six-lens lenses of the Zh and RO series have a ratio of focal length and back focal length of the order of 60-65%, while IPZ lenses of the 35KP series have about 70-75%. Perhaps this was done to remove the lens from the incandescent lamp, perhaps by accident: this optical scheme was very often used when creating standard 50 / 1.4 lenses for SLR cameras, where a large back distance was required. One way or another, the installation of a second iris is available even for the 35KP 65 / 1.8. But among the lenses of the RO series, the ability to control vignetting while maintaining compatibility with SLR cameras is present only for optics with a focal length of 100 mm (PO501-1 100/2).

The lens diaphragm is installed in the lens shank and is regulated by its ring.

The lens diaphragm is installed in the lens shank and is regulated by its ring.

As a focusing mechanism, a 65-25 mm M55 macrohelicoid was chosen, for which a special shank was made with a thread for attaching to the M42 camera and a lens diaphragm control unit.

Adapted 35KP-1,8 / 75 assembly when focusing at infinity.

Adapted 35KP-1,8 / 75 assembly when focusing at infinity.

The stroke of the helicoid is enough to obtain an MDF of the order of 40 cm, which provides a good scale when photographing small objects.

Adapted 35KP-1,8 / 75 assembly when focusing on MDF.

Adapted 35KP-1,8 / 75 assembly when focusing on MDF.

Lenses 35KP-1,8 / 75 have a single-layer coating, mainly of pink-violet shades. The lens turns a little green in the light.

View of the lens in the light.

View of the lens in the light.

The 35KP-1,8 / 75 is a rather convenient lens for adaptation. Due to the large rear section, it turns out to be more massive and more overall than LOMO Zh-53, but it allows realizing the possibility of vignetting control for SLR cameras. A significant drawback of the lens is the high percentage of damaged copies: it is impossible to be sure that a perfectly preserved-looking lens will not be irreparably misaligned if tests were not carried out on the camera before purchase.

Optical quality

A successful copy of the lens has a pretty good sharpness in the center of the frame already with an open aperture. The unsuccessful one is inclined to have pronounced softness due to coma in the center of the frame, which can be seen when examining the focal points and pre-focal points from a point light source. A significant contribution at an open aperture is made by spherical and chromatic aberration... Their influence is noticeably reduced already at aperture down to f / 2-f / 2.8. The level of chromatic aberration is typical for optics of the second half of the XNUMXth century.

Field distortions are corrected quite well, in this the lens is better than the Belarusian 35KP and a number of optics (Soviet and foreign) of the 85/2 class. In comparison with the well-known Helios-40-2, for example, 35KP-1,8 / 75 demonstrates similar sharpness in the center of the frame at equal apertures, but much better at the edges and corners of the frame. Also by itself

35KP-1,8 / 75 has a low level of vignetting, which makes the use of a lens diaphragm really expedient. At apertures of about f / 5.6, the lens has no problem with image quality.

35KP-1,8 / 75 has a single-layer coating and 5 groups of lenses, so it is not very good when working in a backlight and slightly distorts the color in the green-yellow area. The lens tends to catch purple hares and a whitish veil. However, in normal light, there are no problems with contrast.

The optical design of the 35KP-1,8 / 75 gives the lens a characteristic bokeh, reminiscent of the old F / 1.4 fifty-kopeck piece on the crop (which, however, is logical). Those. something unusual in the picture 35KP-1,8 / 75 can hardly be found. The focus discs have a pronounced edging, colored yellow-orange due to spherochromatism (the so-called "bokeh-fringing", usually they did not think about correcting it in projection optics). At medium focusing distances, the distortion of the focus discs in the corners of the frame becomes noticeable under the influence of a coma: they take the form of triangles with their vertices looking from the center of the frame.

The use of a lens diaphragm allows the bokeh discs to be shaped like lemons, i.e. add a swirling bokeh effect. In addition, the use of a lens diaphragm reduces the effect of coma (therefore, conventional high-aperture photo optics often initially have vignetting of the order of 50-60%) and darkens the edges of the image (vignetting itself). Vignetting with a second aperture allows you to achieve a pronounced effect on crop cameras, which is inaccessible for conventional optics. This option makes the result of the 35KP-1,8 / 75 more flexible and interesting.

Most likely, if the variant of the scheme with an increased back segment had not been applied, it would have been possible to achieve a much better level of correction. But the 35KP-1,8 / 75, and with all its shortcomings, deserves the title of one of the best Soviet lenses in terms of optical quality. The cost of the lens unit 35KP-1,8 / 75 in the USSR, by the way, was equal to the price of the lens Jupiter-6 180/2.8.

Below are photos on 36KP-1,8 / 75 and full-frame Sony A7s. A number of photographs were taken in vignetting mode.

Below are photos on the 36KP-1,8 / 75 and full-frame Canon EOS 5D from Oleg Isaev, instagram cat.tangent:

Other movie projection and movie shooting reviews:

  1. RO3-3M 2/50
  2. PO 500-1 F9 CM. 1: 2 P (review from the reader)
  3. 2/92
  4. F = 92 1: 2
  5. ОКП-6-70-1 F=70 1:1,8
  6. LOMO RO501-1 F = 100 1: 2 (+ materials from the reader)
  7. LOMO RO500-1 F = 90 1: 2
  8. 16KP-1,4 / 65 (review from the reader)
  9. 35KP-1,8 / 70
  10. 35KP-1,8 / 75 (review from the reader)
  11. 35KP-1,8 / 85
  12. 35KP-1.8 / 120 (review from the reader)
  13. 35KP-1.8 / 100 (review from the reader)
  14. LOMO P-5 F = 90 1: 2 (review from the reader)
  15. LOMO P-5 F = 100 1: 2 (review from the reader)
  16. LOMO OKS1-22-1 F = 22 1: 2.8 (review from the reader)
  17. ЛОМО ОКС1-40-1 40/2.5 (review from the reader)
  18. LOMO OKS1-300-1 F = 300 1: 3.5 (review from the reader)
  19. LOMO OKS11-35-1 F = 35 1: 2 (review from the reader)
  20. LOMO J-53 F = 75 1: 2 (review from the reader)
  21. LOMO J-54 F = 85 1: 2 (review from the reader)
  22. Tair-41 50/2 (review from the reader)
  23. KO-120 1: 2,1 120mm
  24. KO-90 1: 1,9 F = 9cm (review from the reader)
  25. KO-120M 1: 1.8 F = 120mm (review from the reader)
  26. KO-120M 120 / 1.8 with a diaphragm and helicoid (review from the reader)
  27. KO-120 1: 2.1 F = 12cm (review from the reader)
  28. LENKINAP RO500-1 F = 9cm 1: 2 P (review from the reader)
  29. LENKINAP OKS1A-75-1 F=75 1:2 P (review from the reader)
  30. Schneider Super Cinelux 70/2

The names of the lenses correspond to their exact spelling on the body.

Conclusions

The seven-lens 35KP-1,8 / 75 is a descendant of the six-lens LOMO Zh-53 75/2, moreover, it is quite successful: with an increased aperture and an increased rear section, the lens has quite good optical quality and artistic properties. The lens lends itself well to adapting to modern SLR cameras and successfully works with the vignetting control aperture on full frame and crop cameras. Finding a successful 35KP-1,8 / 75, however, can be challenging.

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

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Comments: 28, on the topic: Projection 35KP-1,8 / 75, adapted with the ability to control vignetting. Review from Rodion Eshmakov

  • koba

    According to the given photos, I personally really like this lens. It somewhat resembles pictures from CCTV lenses, only several times better for the full format. I wonder how much such a lens can cost if you find it and remake it for Nikon, for example?

    • Rodion

      You asked me the same thing about 100 / 1.7, but it remained at the level of conversations. This lens is compatible with Nikon anyway. The lens costs $ 300.

      • koba

        Yes, I asked and planned to buy, but at that time there were a lot of unforeseen expenses, I still pay, and I really put this lens in the first place for purchase, as soon as I can immediately order it. I just revisited the pictures from that lens too, they are both great, but I really liked this one. I often use CCTV 25mm / 1.4 on crop and always looked for something similar, but without its flaws on Nikon, now I know that this one is what I was looking for, I did not even hope that this could exist on a full frame, usually revised normal photo lenses, but there are no such explosive bokeh, or there are absolutely correct and excellent bokeh (for example, on the modern Sigma 135 / 1.8), but still without emotion, and it costs like a used car. So, I'm starting to save $ 300.

        • Andrei

          Are there any unexpected expenses in China? Well, that can't be.

          • koba

            Not in China, outside of China. As you probably understand, all people who work outside their country, especially if this country is Georgia and the like, then not only most, but almost all of their salaries and other incomes are sent home to support their families, relatives, etc. In China, there are very few unforeseen expenses.

      • koba

        Rodion, hello! You emailed me today, right?

        • Rodion

          Yes, right.

          • koba

            Thank you!

          • koba

            By the way, I didn't make out from the photos, can I screw a protective filter to it? If so, what size?

            • Rodion

              I didn’t foresee such a possibility in this version. There the lens is not too vulnerable - it doesn’t stick out.

  • Max kotov

    Nice and artistic, I'm impressed

  • enlilA

    I did not speak it.

  • Rodion Eshmakov

    Out of interest, I looked at the product catalog of the Izyum Instrument-Making Plant today. In fact, the glass catalog is almost the same as that of LZOS. Except for OK-4 low-dispersion glass. Products include levels, scopes, optics for armored night vision devices. Too bad they don't even try into civilian products, with the exception of microscopes.
    Website: http://www.ipz.com.ua/index.php?option=com_content&view=section&layout=blog&id=5&Itemid=86

    • Jea reth

      And we, as always, everything sensible to the defense industry goes ... What rockets! Hmm ...
      By the way, you reminded me of one question that I somehow wanted to ask. Actually, recently they were picking a four-wheeled trash in the garage of my friend, who he proudly calls, as it is fashionable now, a “project”. Well, I - just for the company to twist the nuts. During the next smoke break, on the rack I came across such an interesting suitcase among all other trash - khaki color, all military, with the mysterious inscription "PNV-57E". Well, it's clear that somewhere a military night vision device was slammed from somewhere. That one, as it turned out, was intended for mechanized drivers, and in general, in the opinion of people from the network, the device, as it turned out, was not useless (completely useless). In the briefcase lay a completely stunned copy, already without a headset and a hint of live wiring. But I was very interested in the lenses before the image intensifier tubes. On that glass they were killed by some kind of dregs, as if by mold, which is very sad. But then there was an instruction for this wonderful unit. And there, among other things, there was a sketch with an eyepiece cut. A very interesting lens: 9 lenses, the focal point is 37mm ... And what is most interesting - it can be twisted from the eyepiece, sits on the thread.
      That's the question, actually. Have you come across such optics for an hour? There is something for a good resolution in the passport indicated, and in general, the optical scheme is interesting and heaped up some ...

      • Rodion

        There is such a thing. It will not stand on the camera because of the segment, even on the A7. But these are the damn nine-lens 37 / 1.0 Zonnars ...

        • Jea reth

          So that's right, I saw something like a zonnaropod in the first groups of lenses ... I had a feeling that it needed to be shoved right next to the matrix, if it was sitting almost on the image intensifier. Is it really possible not to directly drown in any way like a lens block Yu-12? Or the frame will not fit there? I just didn't unscrew it, didn't check it. And I have nowhere to go with such ROs.
          It is better not to develop this topic though Otherwise, all mirrorless people will start chasing binocular night vision devices like the same cyclops. Avito's price tags will jump up, but airsoft players will not forgive us for this.

          • Rodion

            He will touch the shutter anyway. Even if you drown.

          • Rodion

            Cyclops, by the way, will also be))))

        • Jea reth

          It just would sound powerful - "Lens from NVG, adapted for UPC"!

          • Rodion

            And you don’t spoil, soon you will see everything for yourself)))) I have been dealing with this topic for six months already.

        • Rodion

          Yes, almost a year has passed, however. They say they have been waiting for the promised three years. It got a little faster.

    • B. R. P.

      Once upon a time, glasses were made.

  • Novel

    Rodion, such a question. I bought myself two lenses, 35KP 75 / 1.8 and OKP-1-100-1 100 / 1.8 I want to put both of them on Canon with little blood, the Chinese have an adapter m65 - m42 and LOMO (62.5 mm) - m65. In the middle is the factory helicoid. Which helicoid would you recommend, do they have 17-31, 25-55, 35-90, so that you can use both at once? They are expensive, I don't want to take two.

    • Rodion

      I think 25-55 is better, oddly enough. It seemed to me that he had a larger step.

      • Novel

        Thank you!

        And what about the distance for infinity? It's hard for me to calculate. If we take the minimum of 25 + 3-4 millimeters for other washers, is this enough, a little, a lot? I can drown the tail of the lens into the helicoid, in principle, that is, the distance will be reduced, but I will have to increase it with macro rings on the M42.

        • Rodion

          I think you will find it empirically without any problems when you mount the lens unit in the focuser.

          • Novel

            Thank. I'll try.

  • Rodion

    Added sample photos on EOS 5d.
    By the way, the lens can be purchased from me - ask.

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