Detailed comparative review of the Lomography x Zenit New Jupiter-3+ 1.5/50 lens

Material especially for Radozhiva prepared Rodion Eshmakov.

The standard lens for full-frame mirrorless cameras New Jupiter-3+ 1.5/50 (hereinafter referred to as Jupiter-3+) is an updated version of the very old Jupiter-3 50/1.5 lens, based in turn on the pre-war design of the Carl Zeiss Jena Sonnar 50/1.5 (US2186621, 1938) by the famous German optician Ludwig Bertele. The production of Jupiter-3+ was organized at the Krasnogorsk plant specifically for the Lomographic Society, and since 2016 a certain series of lenses have been produced.

Here I would like to note the funny fact that on the official page of the lens on the Lomograph website Jupiter-3+ is called “a revival from the zenith of Russian optical design,” but it’s Jupiter-3 (unlike the same Russar 20/5.6) has nothing to do with the optical design of the countries of the former USSR - the difference between Berthelet’s original and M.D.’s recalculation Maltseva is ephemeral.

The relationship between KMZ and Lomographs was complicated, and some time after the start of production, Jupiter-3+, without the participation of Lomographs, was transformed into Zenitar 50/1.5 in a dubious by body design.

The “Lomographic” Jupiter-3+ deserves attention at least as a modern reissue of a really popular and interesting vintage lens, but even almost 10 years after the start of production of Jupiter-3+ lenses, there is still no precise understanding of what exactly was changed in the original Jupiter-3 , and how it affected his portrayal. This article analyzes the innovations in the “new” Jupiter-3 relative to the old Soviet one, and also performs a number of comparative tests of image quality and design with other lenses (Jupiter-3 1960s, 7artisans 50 / 1.1, Minolta 58 / 1.4).

All reviews of Jupiter-3 lenses:

1. Jupiter-3 1:1.5 F=5cm P (1952, KMZ). How many different Jupiter-3s were there?
2. Jupiter-3 1:1.5 F=5cm P (1957, ZOMZ), M39
3. Jupiter-3 1:1.5 F=5cm P (1963, ZOMZ), Contax RF
4. Jupiter-3 1:1.5 F=5cm (1972, ZOMZ), Contax RF
5. Lomography x Zenit New Jupiter-3+1.5/50 L39/M (KMZ, 2010s), M39 - detailed comparative review

Specifications:

Optical design – 7 lenses in 3 groups, “Sonnar”;

Focal length - 52.5 mm;
Relative aperture - 1: 1.5;
Field of view - 45 °;
Frame format - 36 × 24 mm;
Rear focal line - ~ 23 mm;
Aperture - 13 blades, without a preset mechanism;
Aperture limits - F / 1.5-F / 22;
Focusing - manual;
The minimum focusing distance is 0.7 m;
Connection to camera – M39 thread (working distance 28.8 mm), pairing with Leica M rangefinder when used with M39-Leica M flange:
The diameter of the thread for the light filter is 40.5 mm;
Weight - ~ 200 g.

Design and execution of the lens

Unlike its predecessor, Jupiter-3+ has a chrome-plated brass body, which is why it weighs about 1.5-2 times more compared to the old aluminum Jupiter-3 (the lens for comparison was provided by Andrey Andrey, inst: entomolog99). The body design of the old and new lenses are identical with the exception of some details.

Thus, a pleasant bonus of the updated version of the lens is the minimum focusing distance shortened from 1 m to 0.7 m. Of course, there is no limit to perfection, and therefore, when using Jupiter-3+ with mirrorless cameras, I highly recommend trying a macrohelicoid type adapter Leica M/NEX  – with it focusing is achieved at an already acceptable ~40 cm. It is good that when the focusing ring is rotated, the lens block of the lens moves only translationally, so there are no problems when using polarizing and gradient filters.

The changed external design is striking, in particular the “modernized” distance and depth of field scales. But such things as a beautiful multi-blade diaphragm with high-quality blackening migrated from the old version to the new one without changes - and good! - A they liked to make “star” lenses at KMZ.

The aperture setting ring rotates steplessly, very smoothly, with a pleasant oily stroke.

Jupiter-3+, unlike Zenitar 50/1.5 with E mount, retains the ability to interface with the rangefinder of cameras of the Leica M and M39 LTM systems. In the new version of the lens, the rangefinder pusher, like the rest of the body parts, is made of brass. Unfortunately, adjustment of the rangefinder pusher is not provided in the lens.

The most important change in Jupiter-3+ is related to the anti-reflective coating on the objective lenses. As you know, old Soviet lenses used in a single-layer chemical coating (based on amorphous silicon dioxide, applied by spin-coating) in a variety of options, depending on the year and place of production of the lens: the same on all lenses or selected for unknown reasons that differed (perhaps the applications were simply not reproducible from lens to lens, from lens to lens) – purple, blue, blue, yellow, who are "infrared» blue, etc. For Jupiter-3, the type of coating greatly affects color rendition, since the lens is quite prone to veiling, and the color of the veil is determined precisely by the color of the reflection of the coating on the “veiling” lens (as a rule, this is the seventh surface). Because of this effect, there is no single “correct” choice of Jupiter-3 lens for shooting, since in different conditions one or another lens option may be preferable.

The updated version of Jupiter-3+ has at least a two-layer anti-reflective coating, which differs for different surfaces. In a direct comparison, it is easy to see that the Jupiter-3+ lenses have less intense reflection than the old Jupiter-3, indicating a lower reflectance at the glass-air interface.

At the same time, visually, the new coating changed little the nature of the light transmission of the lens - both the old and new versions are completely yellow-green.

By the way, in the photo below you can clearly see that KMZ designers or production workers missed the light protection on the ring between the first and second lenses of the lens - it is very shiny, although the old lens does not have this defect.

Even with the naked eye it is easy to notice that the colored veil of light scattering is more pronounced in the old Jupiter-3, while the lenses of Jupiter-3+ seem literally more transparent.

Therefore, one would expect much better performance from the anti-reflective coating of the updated version than from the anti-reflective coating of the old lens.
In general, Jupiter-3+ makes an excellent visual and tactile impression thanks to the choice of expensive materials and high-quality assembly.

Optical properties: some technical information

Using X-ray fluorescence analysis, it was revealed that Jupiter-3+ and the old Jupiter-3 use the same optical glasses. According to available information, the lens has not undergone any recalculation. The optical design of Jupiter-3 (and Jupiter-3+) with minimal differences corresponds to the Ludwig Berthele Sonnar 50/1.5 lens, which is considered a legend and a classic among a number of designers. It is still not entirely clear exactly what method Ludwig Bertele used and based on what principles he considered his lenses, since his design is extremely original and in some cases counterintuitive.

Sonnar 50/1.5 is interesting for a number of design features that make it unique among other “fifty dollars”:

1) The lens uses the best grades of optical glass for its time (1930s). Positive lenses are made of barium flints (BAF10/BF16) and heavy crowns (SSK5/TK21) with the highest refractive index values ​​and the lowest dispersion. Heavy flints (SF3/TF4) with high dispersion and high refraction, and crown flints (KF9/OF1) are also used. With the development of optical materials science in the post-war period, even more attractive glasses appeared, such as heavy lanthanum crowns and flints, and Ludwig Bertele managed to redesign some of his lenses using them, which sometimes led to a serious simplification of the design while improving image quality. It is somewhat unfortunate that KMZ did not follow this path and did not present their alternative to the Carl Zeiss C-Sonnar ZM 50/1.5. And it was possible to do it at all 50/1.0 or 50/1.2 lens.

2) To combat light scattering, the seven-lens optical design uses triple gluing, resulting in the number of glass-air interfaces being six – as in the simplest Cook's triplet. Interestingly, the front triple bonding in the lens is completely artificial: to ensure better quality, it is preferable that instead of a light crown lens (FK5/LK3) there be simply an air gap. That is why neither the modern Carl Zeiss C-Sonnar ZM 50/1.5 nor the 7artisans 50 / 1.1 the anterior triplet is no longer preserved. In addition, triple gluing is a very expensive and labor-intensive element.

3) The lens very actively uses the so-called “Merthe surfaces” (Willy Merthe - German optician, inventor of the optical design Tessar F/2.8 and a number of other systems): bonded surfaces with large curvature, which would not be possible to achieve if there was an air gap due to complete reflection of light. In the case when such a surface separates two materials with similar parameters, for example, glasses with the same dispersion, but different refractive index, or, on the contrary, glasses with similar refraction, but different relative partial dispersions, then it becomes possible to generate high-order aberrations to compensate for more inferior ones formed by other parts of the lens, as well as correction of chromatism. Both approaches to composing the Merthe surface are used in the second bonded component of the Sonnar 50/1.5 lens.

4) The lens is asymmetrical when compared to a typical 50/1.4, made using the “double Gauss” design. This arrangement made it possible to make the Sonnar 50/1.5 one of the most compact high-aperture fifty dollars, if not the most compact in general.

The unusual design of the optical design led to a very specific balance of aberrations in the lens. For example, the longitudinal aberration curve, which is a superposition of spherical aberrations of the third and higher orders, has a very complex form, completely uncharacteristic for other similar lenses. Because of this, the nature of the lens pattern can change greatly with aperture.

Examples of photos taken on Sony A7s and Jupiter-3+ with apertures F/1.5, F/2 and F/2.8 are given below.

As you can see, Jupiter-3 has, by today's standards, disgustingly corrected chromatic and spherochromatic aberrations: at an open aperture, the secondary spectrum is comparable in length to a long-focus lens like Tair-3! And even with small relative apertures, chromaticity will not allow achieving high resolution - this is not Vega 9, whose chromatism is almost three times less.

The main disadvantage of the lens (and, spoiler alert, the reason for its subsequent replacement with “double Gaussians”) is astigmatism. By today's standards, its correction is very poor. Astigmatism of both the third and higher orders greatly limits the image quality across the field.

Due to its asymmetry, the circuit does not control distortion well enough (~ +3%, “cushion”). However, Bertele also proposed an eight-lens version, in which the problem was partially solved.

The following are graphs of the contrast transfer function at frequencies of 10 lines/mm and 30 lines/mm for the spectral range of 400-700 nm (based on the spectral sensitivity function of the Sony A7R2 matrix) at F/1.5, F/2 and F/8.

As a purely artistic lens, Jupiter-3 is not so bad today, but, of course, its level of optical quality is completely insufficient to use it for everyday shooting: even with an aperture closed to F/8, the lens does not provide a good level of quality across the 36× frame field 24 mm. It would probably be a very good idea not to use the 1930s design as is, but to recalculate it using modern brands of optical glass (even the LZOS catalog would be enough), which would improve the image quality and make the lens more technologically advanced.

Optical properties: comparison of antireflection of old and updated lenses

Jupiter-3+ and Jupiter-3, as previously noted, even visually differ in the clearing of the lenses, although from the point of view of color rendering it seems similar at first glance. In fact, the difference between the lenses is quite significant. Thus, the old version of enlightenment, as it turned out, shifts the image tone to a greater extent to the yellow-green area.

In addition, it was found that the values excerpts with Jupiter-3+ are 1/3 of a stop shorter than with Jupiter-3, in the same use scenarios. This observation allows us to normalize the transmission spectra of the Jupiter-3+ and Jupiter-3 lenses for subsequent comparison.

Below are paired examples of photos from Jupiter-3+:

And for the old version of Jupiter-3:

The updated lens in most situations provides a more contrasting image with less color distortion than the old Jupiter-3, although, it seems to me, if it also had a nut between the lenses without glare, it would be even better.

Optical properties: comparison of the pattern with the Sonnar-like 7artisans 50/1.1

Among the available modern lenses with Sonnar optical design, it is, of course, worth mentioning the Chinese 7artisans 50/1.1 Leica M, in the review of which some comparison with the old Jupiter-3 lens has already been given. Here I will add a few photos to compare it with the Jupiter-3+ lens at apertures F/1.1 and F/1.4:

And paired photos on Sony A7s and Jupiter-3+ at F/1.5:

It’s easy to notice that the bokeh of Jupiter-3+ is “brighter” than that of 7artisans 50/1.1, but it cannot be said that some of them are better or worse. One of the advantages of Jupiter-3: its bokeh does not deteriorate towards the corners of the frame, as in the case of the Chinese Zonnar. Note also that a modern Chinese lens works much better in backlight, despite a more complex optical design with a large number of glass-air boundaries: in the 7artisans 50/1.1 with coating and light protection, everything is really good, but the KMZ was either cheated or not then we saved.

Optical properties: comparison of the pattern with the Planar-like Minolta Rokkor 58/1.4 MC

It would seem, what is the point of comparing Zonnar with a typical 6/4 “double Gauss”? In fact, there is no other “Planar” that would be as similar to Jupiter-3 as Minolta 58/1.4. The bokeh of the lenses is very, very similar in the central area of ​​the frame, roughly corresponding to the APS-C frame. At the same time, Minolta 58/1.4 has better correction of spherical aberration, therefore its blurring in the central part is somewhat less provocative than that of Jupiter-3+. It’s easy to recognize lenses by the bokeh in the corners of the frame: Minolta, as befits a “planar”, has corrected astigmatism, which is why the bokeh discs remain neat little lemons even at the edge of the field.

Examples on Sony A7s and Minolta MC Rokkor-PF 58/1.4:

And paired photos on Jupiter-3+:

In general, if you really like the Jupiter-3 design, but you are not satisfied with its optical quality, the Minolta 58/1.4 will be an excellent alternative.

Optical properties: lens sharpness test at infinity

Testing of image quality when focusing at infinity was carried out for four lenses: Jupiter-3+, Jupiter-3, Minolta 5/1.4 MC and 7artisans 50/1.1. Each time the aperture was changed, refocusing was performed. Photos were taken on a full-frame Sony A7s camera.

Full-size cloud test results here.

Based on the test results, we can conclude that there is no difference in image quality between the old and updated Jupiter-3 - apparently, the assembly of the current KMZ could not spoil the lens. The Chinese 7artisans provides the best image quality among the tested lenses at apertures greater than F/2 in the central area of ​​the frame, but at the edges of the field it is no worse than the Jupiter-3. In general, in terms of image quality, the most balanced lens is the Minolta 58/1.4, with which it is easy to achieve sharpness even in the corners of the frame.

User experience

Lenses with Sonnar optical design have always been attractive to me because of their eye-catching images, interesting parameters and legendary history. Jupiter-3 was one of the first lenses that I ran to buy after purchasing Sony A7s, since then I have owned more than five different Jupiter-3 lenses and even one Carl Zeiss Jena Sonnar 50/1.5 T. The capriciousness of the Jupiter-3 and its very compromised optical quality often forced me to try to find an alternative to it - the same 7artisans 50/ 1.1, Minolta 58/1.4, for example.

However, practice shows that in real work these lenses are not quite equivalent to Jupiter-3; often it is simply impossible to get from them some memorable effects characteristic of Jupiter-3: colored flares, an interesting veil in some cases, crazy scattering in all directions bokeh The updated version of the lens turned out to be much more convenient to use compared to the Soviet Jupiter-3, and this is largely due to the anti-reflective coating - after all, there are no other changes in the optics. New Jupiter-3+ allows you to get everything that you can get with the old Jupiter-3, but a little easier.

The following is a gallery of photos taken with the Lomography x Zenit New Jupiter-3+ 1.5/50 and Sony A7s.

Conclusions

Jupiter-3+ is a classic, Ludwig Bertele, Sonnar, bokeh and all that. But despite the fact that the lens is in a number of aspects better than the old Jupiter-3, nowadays it is clearly felt that this classic is quite outdated, and releasing such a lens “as is” without a significant revision and rethinking of the optical design is interesting, but not the best idea. One way or another, Lomography x Zenit New Jupiter-3+ in perfect condition has a far from exorbitant price on the secondary market, very often comparable to early versions of Jupiter-3 in good condition, and therefore for a connoisseur of the good old Sonnar 50/1.5 it can become great find.

10 main advantages

• Recognizable and pleasant appearance;
• High-quality and expensive body materials;
• High-quality assembly of the mechanical components of the lens;
• Smooth, pleasant movement of the focus and aperture rings;
• Very small lens dimensions;
• Round aperture at any relative aperture value;
• Unusual, expressive bokeh;
• The best and newest of the Sonnar 50/1.5 mod. 1938
• Interesting image artifacts in backlight;
• Universal M39 LTM mount.

10 main disadvantages

• There is no possibility of adjusting the rangefinder pusher;
• Optical design without the use of modern materials;
• Inconvenient metal front cover without latches;
• Produced by the current KMZ is not at all a guarantee of high-quality assembly of optics;
• Long minimum focusing distance 0.7 m;
• Excessive angular travel of the focusing ring (180° would be sufficient for a given MDF size);
• Chrome plated brass is beautiful, but heavy. A real luxury would be titanium;
• Insufficient light protection of the lens (poor quality of blackening of internal surfaces);
• Very pronounced aberrations of all sorts, excessive by any modern standards, and high vignetting;
• There is no way to achieve field sharpness even with aperture.

You will find more reviews from readers of Radozhiva here.