I-26m (Industar-26M) 52 / 2.8, redone for EF mount with preservation of infinity, a review from the reader Radozhiva

Overview of the I-26m (Industar-26M) 52 / 2.8 lens, redone for the EF mount with preservation of infinity specifically for Radozhiva prepared Rodion Eshmakov.

I-26m

I-26m

TECH SPECS

Design: four lenses in three groups (Tessar), ordinary glass types
Resolution (center / edge): 27/18 lines / mm (sometimes attributed to 30/12 lines / mm)
Vision angle: approximately 45 degrees
MDF: 1 m (ordinary sample), ~ 0.3 m (converted sample)
Aperture limits: F / 2.8-F / 22
Diaphragm: 10 petals, manual control, continuously adjustable ring
The weight: slightly more than 100 g
Years of issue: 1950-1960s (FED)

Industar-26M, also known as I-26m, is a standard lens for М39 thread (28.8 mm cut) for rangefinder cameras "FED-2" and "Zarya". IN normal form it is suitable only for mirrorless cameras (on the ZK it works only in macro mode), however, here you can find an example of a lens made for the EF mount.

I-26m

I-26m

The lens is very widespread and affordable, but requires radical alteration for use on a SLR camera: it is necessary to shorten the helicoidal part, deepen the lens unit, having lost the normally functioning ring with the depth of field scale. In addition, the lack of reserves in the design does not allow using the “native” focusing mechanism to the full:

  1. The focus ring is attached rigidly to the bayonet ring (I had an M42-EOS adapter) to connect to the camera.
  2. Focusing is carried out by rotating the lens unit rigidly fastened to the helicoid screw - i.e. when focusing, the entire lens unit rotates.
  3. There are no MDF stops, which in this case is only a plus: the MDF of the lens reaches 0.3 m, but you need to be more careful - when focusing, the lens unit can be easily unscrewed from the helicoid)

After working on the helicoid, the lens turns into a "pancake" like And-50... However, they are extremely uncomfortable with focusing - there is nothing to grab onto. Therefore, we use a ring with depth of field scales: for grip, we attach it to the 40,5 thread for filters. To use filters, we attach an empty frame to the installed ring.

A significant disadvantage of this alteration is that the diaphragm ring becomes too uncomfortable - it is narrow, sometimes gets confused when focusing, difficult to reach at infinity and long distances.

The alteration process was described in detail even before me, in the article “Industars in tailcoats“, On the Futazhik website, for which many thanks to them. The rework process is quite simple, although it requires ingenuity and basic tools. Specific things like machining on machines are not required.

As a result, we get a lens with bayonet mount, small MDF, simple focusing, uncomfortable aperture, small dimensions and weight. Let's see what he is capable of.

I-26m

I-26m

Image quality

The lens has very mediocre sharpness on an open aperture (strong soft effect), although it seems sharper Industar-29, which does not have software, but simply “soap” - because details are indistinguishable at all. The I-26m forms a simply smoothed, soft picture. Although sometimes the sharpness is not enough.

The contrast of the lens is very sluggish, it is very afraid of flare. However, the ring with the depth of field scale and the ribbed cone-shaped rings reinforced in it (extracted from the dead lens units G-44M, usually stand between the lenses) still protect the lens from light, creating for it something like a lens hood.

At the edge of the lens, the sharpness of the lens drops due to a coma - characteristic “birds” will appear at the edge of the full frame. Due to geometric vignetting (50%) and coma, the lens slightly curls the background. Sharp high-quality detailed (after all, the lens has a Tessar scheme!), The image can be obtained from an aperture of F / 8, up to F / 4 the lens has strong software.

It would seem - a very disappointing characteristic. However, the lens, thanks to this “blend” of aberrations, forms a very interesting image - extremely soft, “luminous”, but at the same time - the lens retains many details behind the software. Such properties turn Industar-26m into an interesting short portrait with a soft, pleasant pattern.

The lens has an interesting background blur - the bokeh is similar to Triplet; a circle with a bright edging, sometimes a light spot is noticeable in the center of the circle. Very typical bokeh for old, under-corrected lenses.

The lens pattern is formed by spherical aberrations, which means it is highly dependent on aperture. In other words, the lens has a plastic picture. A round ten-blade diaphragm allows “lossless” (no nuts) to control this plasticity of the pattern; the fact that it can be closed down to F / 22 is a good surprise for macro fans when depth of field is always lacking.

Download source files in format JPEG can at this link (14 files in the '.JPG' format, 116 MB). All photos were shot on Canon 600D.

Conclusion

Industar-26M is a rather interesting very affordable old lens, a representative of “warm tube” “dolanthan” Tessars, which requires serious alteration for use on SLR cameras. The lens has a very soft and interesting pattern, which allows it to be used as a short soft portrait lens. On the other hand, due to its weak sharpness and low contrast, the lens is not recommended to be used as an everyday fifty dollar lens. His younger brother, Industar-61 LZ MS, is more suitable for this role.

Thank you for attention. Eshmakov Rodion.

Addendum to the adapted Industar-26M review

It so happened that I suddenly missed this small lens: the attractive dimensions and the picture, the successful adaptation of the Industar-61 L / D (which had to be removed often - he was always with him) forced me to search again for a suitable copy.

The lens was found and adapted in the state as new; during the alteration noticed some features.

Given the outwardly perfect appearance of the lens, it was surprising to find metal shavings inside, teases in a helicoid and other delights. This all speaks of a very low production culture at the FED.

In addition, it turned out that, unlike the I-61 / D, the I-26M facets of the lenses were not blackened, which was corrected. Let me remind you that saving on such a penny operation as blackening of chamfer lenses de facto kills all the efforts of opticians to create perfect antireflection coatings - non-blackened chamfers often cause bizarre glare (remember what circles Zenitar-S 50 / 1.2s burns out) and appearance veils.

The lens was adapted in exactly the same way as the Industar-61 L / D from the review (https://radojuva.com/2016/03/industar-61-l-d-2-8-55-fed/), the difference is the need to grind the "nut" of the helicoid by ~ 1 mm in order to get infinity with M42. This time the ring with the depth of field scale was not used, as its installation as a focusing ring deprives the lens of one of the important advantages - compactness.

So the lens looks in comparison with the adapted Industar-61 L / D:

I-26m

I-26m

I-26m

After comparing both lenses (http://lens-club.ru/reviews/item/c_48.html), we can say that the sharpness in the center of the frame of Industar-26M is really low, but not much behind the sharpness of Industar-61 L / D with equal apertures. At F / 2.8, quite strong software is observed, at F / 4 it still has a noticeable effect, at F / 5.6 the long-awaited sharpness begins. At F / 8, the lens is very good in the center.

At the edge of the frame, the Industar-26M has very, very weak sharpness due to the presence of a strong coma (typical of old tesars and triplets - Domiplan, Industar-22). Covering the aperture gives an improvement, but insignificantly - only to F / 11 at a crop of 1.6 (!) Edges and corners are completely corrected, even F / 8 is still not enough.

Meanwhile, in contrast and color, the lens after blackening the bevels pleased - in the absence of sun in the field of view, the contrast is very good, and the colors are bright and natural. In the presence of a powerful light source in the field of view, the "sunny rain" objectifies:

objectifies the "solar

objectifies the "solar

Or bizarre glare from enlightenment:

objectifies the "solar

Point bright light sources also cause glare-flies in the frame - such as small bright spots, which is a disadvantage of the lens.

The lens, despite its flaws, still seemed very interesting to handle. Working with a brand new, not beaten copy revealed more advantages, including good contrast and "correct" colors, an interesting pattern and excellent plasticity. But, of course, it is worth remembering that the lens can manifest itself only after correcting factory defects: a banal replacement of lubricant and cleaning of the helicoid and lens unit, blackening of the lens chamfers is extremely necessary for each copy. In addition, lenses vary greatly in quality - only a patient amateur will find his Industar-26M, which will delight him with beautiful photographs)

A list of all reviews from readers of Radozhiva will find here.

Save

Save

Save

Save

Save

Add a comment:

 

 

Comments: 18, on the topic: I-26m (Industar-26M) 52 / 2.8, redone for EF mount with preservation of infinity, a review from the reader Radozhiva

  • Lynx

    Damn, it was such a beautiful, warm, lamp makrik for the Central Control Commission.
    Took and broke. what for???

    • KalekseyG

      Well, a makrushnik with a soft, not contrasting, low-resolution picture? I doubt it!

      • Rodion

        At F / 8 it is very sharp.

    • Rodion

      They did not break it - they gave a second life to the beaten and literally discarded copy. Now this lens pleases another owner

  • Dmitriy

    add two points from personal experience
    1. I-26 has a noticeable variation in parameters. therefore, you can meet and very soft and quite sharp with open specimens.
    2. The optical advantages of this type of lenses are a cocktail of its disadvantages. one of the most interesting in practical terms defects is the appearance of chic sunny “hares” while maintaining the overall contrast of the image. such tricks are obtained not with all I-26s. besides, different "rabbit generators" give different "products". some are in the form of arcuate stripes, others are cones.

  • Felix

    Rodion, well done! Great alteration, excellent visibility. I will support the previous commenter about the scatter of I26. I came across 26 that were quite a bit inferior to the industry 61 by 2.8 and were already indistinguishable on f4 and were not even afraid of the backlit ..

  • Rodion

    I found the I-26m significantly more interesting than the I-61. My I-61 with 10 blades was even worse in sharpness and contrast.
    Somehow I'll remake the I-61 L / D late ...

    • Felix

      I advise you to blacken the facets of all owl optics.

      • Rodion

        Already ...

  • Tessim

    BDSM with a good b / w lens

  • grandfather

    RODION RESPECT +++

  • grandfather

    TO ME I HAVE A LITTLE OF GLASS I ARE ATTRACTED BY LANDSCAPES AND STREET PHOTOS. I ADVISE THE REGION TO BECOME THE OPTICS OPTICS MANAGER IN THE POST OF THE USSR. ONLY THE BEST WISHES.

  • Fedor

    Maybe I repeat, tk. I didn’t read all the comments on the reviews “from Rodion”, lenses for FF and test on FF, it’s not enough that the edges can get out. I won't say anything about the medium format :-)
    Behind the review, thumbs up.

    • Rodion

      There will be ff - there will be a review on ff. The rich they are, the more happy they are.
      There is no full-fledged review of the I-26m yet, much less on ff - even on the crop.

  • SpongeBob

    Projection lens for small format enlargers. Appearance and size as the lens "Industar-50U." The price in the mid-1980s is 9 rubles.

  • Rodion

    The review was supplemented by a small amount, more photos were added for a better and safer sample.

  • Alexander

    Yes, they can only shoot ants without alteration. Only the diaphragm works. It is useless to turn the focusing ring, you can shoot only by zooming in or out from the subject, which is very inconvenient. Remained the same by inheritance - born in 1953, i.e. made in the year of the death of the father of nations. The bokeh is of course beautiful, what's the use if they can only take off small flowers, it's not worth talking about a portrait.

Add a comment

christening photographer price Photography for lovers

Copyright © Radojuva.com. Blog author - Photographer in Kiev Arkady Shapoval. 2009-2021

English-version of this article https://radojuva.com/en/2016/01/i-26m-industar-26m-52-2-8/