Industar-26m 1: 2,8 F = 5 cm P (FED). Review from Rodion Eshmakov

Overview of the Industar-26m lens 1: 2,8 F = 5 cm P (FED) specifically for Radozhiva prepared Rodion Eshmakov.

Industar-26m and adapter M39-NEX.

Industar-26m 1: 2,8 F = 5 cm P (FED) and adapter FOTGA M39-NEX. increase.

No one has seen Industar-26, but very often you can find a regular lens for range-finding cameras Industar-26m, which was produced in large quantities at the plant named after F.E. Dzerzhinsky since 1955 for more than a decade. The review presents an early “lead-in” version of the lens of the 50s with modifications made to reduce the minimum focusing distance.

Technical specifications (source):
Optical design - Tessar, 4 lenses in 3 groups;
Focal length - 52 mm;
Relative aperture - 1: 2,8;
Light transmission coefficient - 0,8;
Vignetting - 50%;
Rear focal line - ~ 41 mm;
Aperture - 10 blades, without a preset mechanism;
Aperture limits - F / 2.8-F / 22;
The minimum focusing distance is 1 m (factory), 0.4 m (achieved by modification);
Thread for filters - 40.5 mm;
Mount - M39.
Other standard Industar lenses for small format cameras can be viewed as a list here.

Industar-26m 50 / 2.8 was calculated by GOI in 1946 (OF-188 in the catalog of GOI), at about the same time a simpler Industar-22 50 / 3.5 was developed. The lens was first produced in small series at the KMZ from 1954 to 1957, and it was intended for the rare Zorky-2 camera. A very small number of Industar-26m was released in the frame for Zenith SLR cameras. Since 1955, the production of the lens began at the FED factory, they were equipped with the FED-2 rangefinder cameras and the Zarya scale cameras.

The Industar-26m, apparently, is not a copy of the German Tessar; for its calculation, a much poorer Soviet optical glass palette was used. However, it was only in the early 1970s that the obsolete I-26m was replaced by the more modern Industar-61, in which lanthanum glasses were first used. In other words, Industar-26m belongs to the family of the fastest Soviet tessars built using the most “ordinary” varieties of optical glass - just like Industar-29 80 / 2.8 for 6x6 cm format, Industar-24 105 / 3.5 for format 6x9.

Design Features. Reducing the MDF lens.

The Industar-26m case is made of unpainted duralumin in the style typical of old Soviet lenses. Early Industar-26m is characterized by a smooth focus ring and the presence on it of the so-called. "Leash"; the later version has a nut-shaped focus ring. In addition, the name of the later lenses on the title ring is reduced to "I-26m."

Industar-26m lenses: early (left) and late (right) options.

Industar-26m lenses: early (left) and late (right) options.

Due to the nature of the rangefinder cameras, the Industar-26m has a large MDF for a fifty-fifty meter, equal to 1 meter. This is a significant limitation, which often makes the use of the lens inconvenient on modern cameras. However, the design of the lens allows you to make changes that reduce the MDF by at least half.

To do this, you first need to get rid of the MDF stopper, and then you need to change the way the lens focuses: unscrew the screw in the rangefinder pusher and fix the shank and focus ring together, we will focus the lens by unscrewing the entire lens block, as was done in the simplest type lenses Industar-50. The ring with the DOF scale will now be used as the focusing ring, but it’s more convenient to screw an empty frame from the filter onto the lens nose and use it (a similar technique is applicable and when adapting the lens for SLR cameras ) A side effect of the alteration is the ability to unscrew the lens block completely from the helicoid, however, this requires one and a half revolutions - the maximum focusing stroke during modification is more than doubled. The lens still remains compatible with rangefinder cameras, if during the alteration, the exact rear segment and the position of the pusher when focusing at infinity were saved. The second is a difficult condition, so it will be easier if you need to reconfigure the range finder, if the camera allows you to do this quickly (FED-5, for example).

Modified Industar-26m when focusing on infinity, when focusing on 1 m and with MDF ~ 0.4 m.

Modified Industar-26m when focusing on infinity, when focusing on 1 m and with MDF ~ 0.4 m.

Changing the aperture value after decreasing the MDF becomes less convenient, because it is associated with the risk of losing focus. Therefore, it is preferable to first expose the desired aperture, and then focus. The diaphragm control ring is close to the nose of the lens and has a corrugation that allows you to find it by touch. The Industar-26m diaphragm itself is equipped with 10 dark petals and always forms a round hole, which is a big plus.

View of the closed diaphragm Industar-26m through the front lens.

View of the closed diaphragm Industar-26m through the front lens.

Industar-26m has enlightened optics, as indicated by the letter “P” in the marking (subsequently, enlightenment became the rule, not the exception, and the letter disappeared). The lens coating has a yellow-pink-purple hue, because the light transmission of the lens is slightly higher in the yellow-green region. The thickness of the antireflection coating of the lenses was chosen for this specimen successfully, although there are "blue-eyed" lenses with pronounced yellowness.

View of the entrance pupil of the lens with a covered aperture.

View of the entrance pupil of the lens with a covered aperture.

Below are more photos of the modified Industar-26m lens.

The Industar-26m has a very successful design: it is very simply arranged (ease of maintenance), and its focusing mechanism has large reserves. This allows not only to reduce the MDF of the lens, but also to remake it for a SLR camera. All Industar-26m equipped with a wonderful round aperture with dark petals, which should have a positive effect on the side of the lens. Most Industar-26m have a well-selected lens brightening, introducing minimal deviations in the transmission spectrum of the lens.

Optical properties

Industar-26m forms an image softened by spherical aberrations on an open aperture, while a coma at the edges of the frame is especially noticeable on a full-frame camera. Chromatism is almost imperceptible (masked by SphA), usually manifests itself in macro photography on a large scale. Resolution in the center of the frame on the open aperture can be considered satisfactory. The sharpness in the center of the frame becomes maximum at F / 5.6 by reducing spherical aberrations. Aperture up to F / 5.6-8 leads to good field sharpness on the APS-C camera, a full aperture will require a decrease in aperture down to F / 8-F / 11.

Under normal shooting conditions, the Industar-26m has a good contrast, but in the backlight you can often see the appearance of a veil and “sun rain”. Veiling can be significantly reduced by blackening the chamfers of the lenses of the lens. From bright light sources, the Industar-26m sometimes catches “flies”. In general, the lens works with light no worse than other old optics - quite satisfactorily.

The color reproduction of the lens is good, close to neutral, which is the result of well-chosen enlightenment and the absence of yellowing rare earth or lead glasses.

The Industar-26m has a pleasant bokeh, which is noticeably softer than that of the Industar-61: the bright edging of the circles of confusion of the Industar-26m is thinner, which makes the ghosting of lines and other bokeh artifacts less pronounced. Due to field aberrations and geometric vignetting, one can notice a slight “twisting”, which, however, is distinguishable from Heliosovsky in character due to the different shape of the circles of blur and the distribution of brightness over them. The picture that the lens gives can be called original.
Below are examples of photographs on the Industar-26m and the Sony A7s full-frame camera (shooting in RAW, processing in Imaging Edge).

Conclusions

Industar-26m is a pleasant lens of the era of the 50s. It has good potential when used on modern SLR and mirrorless cameras, although it requires some effort. This lens is definitely worth a try if you are a lover of the good old tessars.

You will find more reviews from readers of Radozhiva here.

Add a comment: B. R. P.

 

 

Comments: 9, on the topic: Industar-26m 1: 2,8 F = 5 cm P (FED). Review from Rodion Eshmakov

  • B. R. P.

    Thanks for your review. Lies like that, though in a terrible state - all loose and muddy. And there is a FED-2.

  • Vladimir

    And how is it different from And 50?

    • Rodion

      In general, to all, in addition to obvious communities. Lighter, harder, softer.

  • vvs

    Does it meet two at the same time? What a nimble kid

    • Neo

      - let me show my industar
      - not at all
      - I have two of them!
      - then I'll come with a friend

  • Sergei

    At Industar-26m there are quite a few varieties.
    http://www.sovietcams.com/index.php?368864500
    Although the absolute championship in the production was held by the famous plant FED.
    But this lens has one very important distinguishing feature (in contrast to Industar-61, which was 99,9% produced in black).
    The Industar-26m was produced only in a silver design, so I would advise our amateur photographers not to suffer with the problem of choosing - I-26m or I-61.
    If a black lens looks more aesthetically pleasing for your mirrorless lenses, then take the I-61.
    And if it is silver (it can still be polished!) - then I-26m.

  • Paul

    Why redo it? It’s rare when you need to shoot something closer than 1m, and for such cases you can install a couple of macro rings.

  • Massimo

    I have this lens for Kiev/Contax RF. I can't find it anywhere. Do you know it? Many thaks. Massimo

    • Rodion

      It is not factory manufactured but modification it is very easy to install I-26m lensblock in Contax RF Jupiter-8/8M bayonet part – they have definately same screw mount and similar working distance

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