Rodenstock Rodagon 1: 2.8 f = 50 mm lens overview specifically for Radozhiva prepared Rodion Eshmakov.
Rodenstock Rodagon on Sony A7s camera. increase.
Rodenstock is known not only for fashionable glasses. The German company is famous for its high-quality technical and format lenses. This article presents one of the most ordinary small format zoom lenses - the old version of Rodagon 50 / 2.8.
Technical specifications
Optical design - 6 elements in 6 (!) Groups (see).
Focal length - 50 mm;
Relative hole - F / 2.8;
Aperture - 5 blades, the minimum value of F / 16;
Working segment - 43.5 mm (when focusing on infinity);
Mounting thread - M39;
Thread for filters - 40.5 mm;
Features: does not have a focusing mechanism, optimal magnification 2-15x, work with backlight aperture scale.
It is surprising and annoying that there is a typo in the company brochure: instead of MTF charts for Rodagon 50 / 2.8, charts for Rogonar-S are shown. View brochure.
Features of the design and use of the lens
Photographic magnification optics do not have their own focusing mechanism due to their scope, however, this does not mean its inapplicability as a regular lens. While SLR cameras allow the full use of such lenses with a focal length of more than 50 mm, short-focus lenses can be mounted on mirrorless cameras while maintaining the ability to focus to infinity. In particular, I used a 25-55 mm macrogeloid with an M42-M42 mount and M39-M42, M42-Sony E rings (thin) - in this case there is almost no overshot for infinity.
Rodenstock Rodagon 50 / 2.8 and macrogeloid 25-55 mm.
The stroke of the helicoid is enough to provide MDF of about 30 centimeters.
Rodagon 50 / 2.8 when focusing on infinity.
Rodagon 50 / 2.8 when focusing on MDF.
Interestingly, this lens can also be mounted on Canon SLR crop cameras, but in this case a more complicated adaptation procedure is required. On a full-frame SLR camera, it is not possible to install a lens with focus on infinity due to the small back focal length.
Side view of the Rodagon 50 / 2.8. Pay attention to the back group of lenses.
The lens itself is simple, but convenient: the case with plastic elements has an “inverted” aperture scale (due to a different orientation of the lens relative to the user when used on the photo magnifier), applied to a wide rubberized ring. This usually looks like a focus ring, but here it serves to set the aperture. The ring runs very freely, the set value is easy to knock down.
Rodagon 50 / 2.8 has a matte five-petal diaphragm, which, when closed at a half step, immediately creates pentagonal “quality marks” in the side. The minimum aperture is F / 16, which can upset macro enthusiasts. On the other hand, aperture further than F / 8 does not make sense with modern cameras due to diffraction - to increase the depth of field it is worth using software processing - stacking.
Rodagon 50 / 2.8 with closed diaphragm.
The lenses of the lens carry a single-layer enlightenment of blue-violet tones. The lens has a light transmission shifted to the yellow area.
View of the lens to the lumen with a covered aperture.
Rodagon 50 / 2.8 uses a six-lens scheme - in contrast to the photographic magnification tessars and triplets common in the secondary market. The lens circuit is usually depicted with two components glued together, but in reality it seems that the lens does not have glued lenses. At least the back element is definitely split - there is a thin metal gasket between the lenses. This is significant, since an increase in the glass-air boundaries is not useful for optics with single-layer enlightenment. It is worth noting that the used optical scheme is not found among ordinary photography lenses, but it is widely used among reproductive ones. This lens is a great opportunity to get acquainted with its design. On Radozhiv there is also an n-cousin telephotoOlder brother”Of this lens.
Optical properties
Rodenstock 50 / 2.8 is not optimized for use at infinity and has the best performance when shooting at close range. At an open aperture, the lens shows very mediocre sharpness - spherical aberrations strongly influence the image. You can also notice a significant drop in resolution at the edges of the frame due to field distortion. Chromatism is invisible. Disadvantages are most pronounced when focusing on infinity.
When closing the aperture to F / 4-F / 5.6, there is a sharp improvement in optical properties - even at infinity Rodagon has good edges at full frame at F / 5.6.
Lens sharpness at f / 2.8.
Lens sharpness at f / 4.
In the near field, Rodagon behaves better with equal apertures than, for example, Jupiter-3. Unfortunately, I did not have a more suitable lens for comparison.
Cropes photo banknotes at Rodagon, F / 4
Cropes photo banknotes on Jupiter-3, F / 4
The lens has a good contrast under normal conditions, but in backlight it often behaves unsatisfactorily.
Backlit work on F / 2.8.
Backlighting at F / 5.6.
The ability to use iris scale backlighting played a bad joke with the lens: due to the design features of the case, light can pass through it into the camera, while a red light is observed. This is a significant drawback of the lens design when used as a photograph.
The red light (on the left) is leveled by protecting the lens barrel from incident sunlight.
The red light (on the left) is leveled by protecting the lens barrel from incident sunlight.
Due to the pronounced spherical aberration, Rodagon 50 / 2.8 has a very remarkable bokeh: the blur circles have a thick bright edging. When you iris, circles turn into distinctly defined pentagons.
Bokeh Rodagon 50 / 2.8 on F / 2.8
Bokeh Rodagon 50 / 2.8 at ~ F / 5.6.
Below are photos on the Rodagon 50 / 2.8 and Sony A7s. The shooting was carried out in RAW, followed by the development of images in Imaging Edge.
Did anyone recognize the minerals and metals in ampoules in the photo? :)
Conclusions
The photo-magnifying “fifty-fifty” Rodenstock Rodagon 50 / 2.8 is a rather specific lens and can hardly be recommended “for every day”: sharpened for use at short focusing distances, it does not provide the proper quality when working at infinity. On the other hand, the lens really shows itself well in macro photography, and can also be interesting for its intricate bokeh. Or maybe it's better Industar-50U?
You will find more reviews from readers of Radozhiva here.
I have observed the Rodenstock lenses and their properties at the Noritzu and San Marco minilabs. These were lenses somewhat different in properties than those described here. I don't remember the focal length, but they were seven-petal and with excellent multi-layer coating; very solid in appearance and in metal frames almost completely.
The review presents a lens from ~ early. 1980s, belonging to the middle segment (the lower one is the Rogonar triplet and the Rogonar-S tessar). Multilayer enlightenment appeared later. Rodenstock also has much more expensive and high quality optics, for example, the Apo-Rodagon N and D series.
Personally, I only once in my life had contact with a lens from Rodenstock, many years ago, on a format camera, I no longer remember the focal length of that lens, but something from the 150mm region is closer to normal. I remember that they shot about 15 frames, them and another lens, also for format cameras, but from Nikon. Then I was very surprised that, as it turned out, Nikon produced lenses for format cameras. So then there were expectations that the German lens would be better than Nikon, but in reality it turned out the other way around. The Nikon picture on the positive film looked much better across the entire field of the frame. Since then, maybe I personally have a biased attitude towards Rodenstock lenses, that is, I don’t have any illusions about them, although I understand that it would be a mistake to judge all of their lenses from that lens.
So you should try El-Nikkor :)
I have the same one, but it’s a rogonar number of lenses. And a rodagon is bigger and looks different
Interestingly, the closest Soviet analogue of this subject is Vega-11U, how close is the picture quality (with similar adapters).
Although Vega has only five lenses, not six.
I once tested Vega-11 out of interest in comparison with Vega-3: then Vega-11 turned out to be very, very much worse at mid-range in sharpness both in the center and along the edge.
In a word, Vega-11 has pronounced spherical aberrations in the open diaphragm just like Rodenstock.
When I tried to shoot Vega-11U film on the Canon 600D, I noticed that it had significant chromaticity on covered apertures. Rodenstock is better fixed: they even say that by 5.6 there is not much difference between APO-Rodagon-N 50 / 2.8 and Rodagon 50 / 2.8.
One way or another, Vega-11U can be a great alternative. But I was interested in trying out this particular lens because of its design.
But what about the sharpness in comparison with the Tessaras? For example, Industar-96U on 600D easily resolves film, grain is clearly visible throughout the frame at 3,5 aperture. Film of the late 90s, from cheap.
The Tessars are definitely more chromate. As I understand it, the main point of Rodenstock is in his near-symmetric scheme. On a closed aperture, he is spared and coma, but at the same time everything is fine with geometry and chromatism. But while the industar gets rid of the coma and the spherical, chromatism still manifests itself - according to my observations.
Citizens ... and where are the sources?