Kino Plasmat f:1.5 Foc. 2 inch. Pat. Dr. Rudolph Hugo Meyer & Co - Goerlitz & New York Nr. 500656
Kino-Plasmat lenses are seen as almost unobtainable for most of us who don’t have thousands of dollars to spend on old rare lenses. For us common folk we are usually stuck with the smaller Kino-Plasmats, like the 20mm f/1.5, or maybe the 25mm f/1.5 if you are a bit lucky. But these barely cover APS-C.
Overview
| Company | Hugo Meyer & Co Görlitz & New York |
|---|---|
| Country | Germany |
| Year | 1926–1941 (mine is 1931) |
| Type | Fast cine lens |
| Mount | DeVry |
| Focal Length | 50mm nominal / 52mm measured |
| Aperture | f/1.5 |
| Intended Format | 35mm silent 4-perf, 1.33:1 (close to APS-C/S35, full frame equivalent: 72mm f/2.1) |
| Coverage | GFX (full frame equivalent: 41mm f/1.2) |
| Minimum Focus | 0.55 m (2½ inch markings) |
| Filter Size | 39.5×0.75mm (slip on size is 42mm) |
| Back Focal Distance | 34.83mm |
| Aperture Blades | 18 |
| Weight | 422g |
| Build Material | Darkened & black painted brass |
| Optics |
|
I once got to hold a Kino-Plasmat 50mm f/1.5 when visiting an old northern lights observatory above the Arctic Circle in my home country of Norway. Ever since then I’ve always dreamed of finding one for a reasonable price.
That day came much faster than expected, like any good lens find.
A person in Arizona happened to sell a DeVry 35mm cine camera for a very reasonable price. It was in used and moldy condition, and he didn’t mention any lenses. But the lens in the pictures looked interesting. I could barely make it out, and I couldn’t see any labels or text because it was taped over with some makeshift lens hood. The images were small and compressed, so I spent a day comparing and measuring as best I could.
In the end I was convinced this was a Kino-Plasmat lens.
The problem was that he was only willing to sell the camera if I could pick it up in Arizona, and I live in Norway. So I found different Facebook groups in the area and asked if someone could buy the camera for me and send it to my brother in law in LA. Most people ignored the request, but one very nice older lady wanted to help me.
I paid her more than what I paid for the lens. I also tried to pay the seller more, but he was comfortable with the low price he had offered. In the end I paid around five times more for shipping, handling and fees than for the actual lens.
I was very lucky to stumble upon this lens, and even luckier that so many people were willing to help me get it. In the end it took around 80 days for the lens to reach me. I didn’t know the condition of the lens. I didn’t even know if all the glass elements were there. This, as you can imagine, was pure torture.
What This Lens Is
This is a Hugo Meyer & Co Kino-Plasmat 2 inch f/1.5, made for 35mm cine use and mounted on a DeVry camera. My serial number research suggests it was made around 1931.
The lens is much more usable than I expected. It covers the full Fujifilm GFX sensor at infinity, with an image circle of around 58mm. It is not sharp in any modern sense wide open, but it has a very beautiful center, strong field curvature, some swirl, glow around highlights and a much larger image circle than the Carl Zeiss Jena Biotar 5cm f/1.4.
This is not a perfect lens. It is a lens from the late 1920s optical speed race, pushed to the edge of what was possible at the time.
History of the Kino-Plasmat f/1.5
Paul Rudolph invented the Plasmat optical design all the way back in 1918 for large format photography. In late December 1923, Dr. Rudolph improved the speed of this design to f/2, introducing the Kino-Plasmat f/2 series for cinema use.
The Kino-Plasmat wasn’t the first f/2 cinema lens. Ernemann had already made the Kinostigmat f/2 for the Ernemann Kino II 17.5mm camera back in 1907. By 1924 lenses like the Rüo-Optik Kino f/2, Goerz Dogmar f/2, Goerz Cinegor f/2, Ernemann Ernostar f/2 and Astro Tachar f/1.8 already existed.
Early in 1925, Dr. Rudolph started development and refinement of a new concept that would later become the Kino-Plasmat f/1.5.
In January 1926, Dr. Rudolph managed to push the Kino-Plasmat all the way down to f/1.5, which was a huge achievement. This made it the fastest cine lens in the world at that time. The title didn’t last long, because already in 1927 Willy Merté from Zeiss developed the legendary Biotar f/1.4 cine lens.
A few sources claim the Kino-Plasmat f/1.5 series was launched in January 1925, although the first actual ad I’ve seen is from January 1926.
Several sources state that A. O. Roth was the British representative for Hugo Meyer lenses, including the Kino-Plasmat f/1.5. Roth fitted a lot of Plasmat f/2 and f/1.5 lenses to various cameras, including Leica, Lunar, Roth Reflex and Meyer Speed Camera.
Catalogs, Serial Numbers and Production Notes
Kino-Plasmat f/1.5 lenses were used on many film cameras over the years. Based on ads from 1926, the earliest dedicated US mount seems to have been for Filmo cameras, with the Kino-Plasmat 1 inch f/1.5 in focusing mount.
The first Kino-Plasmat f/1.5 series was available from 20mm to 3½ inches. By 1928, American ads described the Kino-Plasmat f/1.5 as a universal lens, corrected for color photography and suitable for Kodacolor film.
Kodacolor back then was a lenticular additive color home movie system for 16mm film, introduced in 1928 and later made obsolete by Kodachrome. In 1928, you could also get Kino-Plasmat lenses for Victor, DeVry, Kodak B and Eyemo cameras.
I took the time to go through all the Kino-Plasmat lenses I could find online, both f/2 and f/1.5, as long as they had a visible serial number. I put everything into a spreadsheet to figure out approximately when these lenses were made.
The earliest Kino-Plasmat I found was a Plasmat 3.5cm f/2, and it was from 1925. The earliest Kino-Plasmat f/1.5 I could find was marked Kino-Plasmat 1⅜ inches f/1.5 and was from 1926.
There seems to be a trend in the production. Some years have no surviving examples that I could find, while other years have higher production counts. Of course this is only based on lenses that have survived and been posted online, so it’s not completely accurate.
| Year | 1925 | 1926 | 1927 | 1928 | 1929 | 1930 | 1931 | 1932 | 1933 | 1934 | 1935 | 1936 | 1937 | 1938 | 1939 | 1940 | 1941 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Units | 1 | 33 | 0 | 0 | 0 | 1 | 54 | 35 | 0 | 0 | 0 | 14 | 1 | 0 | 0 | 0 | 6 |
The first large batch seems to have been in 1926. Then another larger period appears around 1931, which is the year my lens was made, into 1932. Then there is a smaller batch in 1936, and lastly a very small batch in 1941. That is the last year I could find for Kino-Plasmat production.
Out of 146 Kino-Plasmat lenses I logged, 35 were marked in feet. The rest were marked in meters. Of the lenses marked in feet, 13 were also marked with New York. The Kino-Plasmats marked in feet were most likely export models for the US and UK markets.
Correctoscope
Another interesting addition for the Kino-Plasmat f/1.5 in 1928 was the Correctoscope from Hugo Meyer, which was a focusing and exposure meter.
This is one of those accessories that makes sense when you remember how difficult it must have been to focus and expose properly with very fast lenses, especially for Kodacolor. I would keep the full Correctoscope ad as a historical source excerpt near the end of the article instead of placing it in the middle of the main history section.
DeVry Movie Snaps Camera
The DeVry camera this lens came with is an oddball. It has gone through some kind of semi-professional conversion, turning it into a snapshot still camera for street portraits of people.
Officially they called the service “DeVry Movie Snaps Camera.”
Included with the camera are some pamphlets showing the concept and the camera in action. The idea was simple: someone took your photo in the street, and you could send away for three poses in postcard size. The text says “See yourself in the movies,” which is a nice little detail since the camera was originally a movie camera.
The company name on the pamphlet is Snapo Camera Co., with an address in Illinois. For the life of me I can’t find any information about Snapo Camera Co. or the address. I can’t find them in historical records, which is odd. Either it was a fake address, or the street and city names have changed completely.
The pamphlet looks to be from the 1930s to 1940s, so it’s not that old. You’d assume there would be some historical trace of this place.
The DeVry Standard “Lunchbox” Camera was launched in 1926, the same year as the Kino-Plasmat f/1.5 lens series. The DeVry Corporation was based in Chicago, Illinois and was founded by Herman Adolf DeVry, a German immigrant. The DeVry Corporation merged with QRS Corp in 1929.
The mount of my Kino-Plasmat 2 inch f/1.5 is the standard DeVry mount. It is a simple mount consisting of a steel tube and three screws. The lens is attached to these screws in three grooves and twisted to secure it firmly.
Hugo Meyer New York and WWII Confiscation
Hugo Meyer & Co Görlitz & New York was a separate US based company that was the sole distributor of Hugo Meyer lenses in the US. They had a separate logo from the main company in Germany.
These were the US addresses and approximate years they operated:
- 105 W. 40th St. New York, 1926 to 1929
- 245 West 55th Street, New York, 1930 to 1938
- 39 West 60th Street, New York, 1943
Interestingly, in 1943 their assets were confiscated by the US government due to the war. This was a Vesting Order issued under the Trading with the Enemy Act. The US government, through the Alien Property Custodian, was seizing property owned by nationals of enemy countries.
Lists exist online showing exactly which lenses were confiscated, including Kino-Plasmat lenses, with serial numbers and camera mounts.
One can only wonder where these lenses are today.
The Versatility of the Kino-Plasmat Series
Kino-Plasmat lenses were used for more than cinema.
Some very rare Kino-Plasmat 9cm f/1.5 lenses were used on medium format cameras. Some Kino-Plasmat lenses were also tested in the early 1930s for television. But the most fascinating use, at least for me, is how many Kino-Plasmat lenses were used in the Arctic to study northern lights.
I first read about this topic when researching the Astro R.K. f/1.25, which was made by Hugh Ivan Gramatzki at Astro Berlin in 1929, with the patent approved in 1933. Alongside this lens, the Kino-Plasmat 5cm f/1.5 was extensively used.
Both lenses were used to photograph northern lights with specially made Norwegian cameras by Carl Størmer. Because northern lights are usually faint and change shape fast, a fast lens had to be used. Later in the 1960s, Canon 50mm f/0.95 lenses were used, showing how important lens speed was for these scientists.
Some Kino-Plasmat f/1.5 lenses, alongside the Biotar f/1.4, were also tested for radiography, filming and photographing X-ray imagery.
Some Kino-Plasmat 50mm f/1.5 lenses were originally adapted by Meyer to Leica Screw Mount and Contax. These are the most valuable versions of the lens for obvious reasons.
Kino-Plasmat peaked in the late 1920s and early 1930s, and slowly lost relevance by the late 1930s. Dr. Rudolph later started development of the next generation of Plasmat lenses, the Rapid Plasmat f/1.0, but had to stop because of illness. He died in 1935.
The lenses are very rare today. They were special purpose lenses for low light photography, and the series was aimed more at movie studios than normal photographers.
It’s hard to say exactly how the Kino-Plasmat f/1.5 was received by the public, but it seems to have been as respected as other high speed lenses like the Biotar 5cm and 7cm f/1.4. Nowadays, images made with Kino-Plasmat f/1.5 lenses are sometimes seen as very unsharp and messy, making the lenses desirable mostly for collectors.
Clean, Lubricate and Adjust
I received the lens in very rough shape. It had a strange smell, and the lens surface was filled with fungus, dirt and grime. It was so dirty I had no idea what condition the optical elements were actually in.
Both the aperture and focus were stiff and could hardly be moved. Not only that, the different threads around the whole lens were stuck. There were three visible screws and they were all rusted, so opening up this lens for a full CLA was going to be hard.
I first tried to remove the lens hood, as this was also stuck. The front threads are 39.5mm with a normal 0.75mm pitch, standard ISO metric 60 degree. I had a pair of strap wrenches that I’ve used before. They are usually safe to use, as long as you don’t use all your force.
In the past I had a little accident where one of the barrels I tried to open started deforming. So to avoid deforming the lens hood, I measured the inside and 3D printed a thick little cylinder for support, which I could insert into the hood. With this and a tiny bit of WD-40, I managed to free the lens hood from the lens.
From there I could clean the front element, which was the dirtiest. For this I used what I always use: Zeiss lens cleaning solution, a new Zeiss microfiber cloth and some q-tips. First I used a small cleaning blower to remove any hard debris from the surface. Then I gently used a q-tip dipped in cleaning solution to remove more dirt, because I didn’t want to rub solid particles into the glass and scratch it.
Lastly I used the microfiber cloth and more cleaning fluid. After that I could see some old cleaning marks, which wasn’t surprising. The rest of the elements were very clean. The fungus came right off with this standard method, which is common for these non-coated lenses.
For the rest of the threads I also had to use the strap wrenches, which worked fine. I’m not sure why these were so hard to unscrew, but I saw a thin layer of old dried liquid. It almost looked like old milk, very strange. This came off with water and soap.
Another small detail was that some of the internal structural threads didn’t use the standard ISO metric thread system. They used Whitworth, also known as BSW, which some lens nerds may have heard of, as the original Leica screw mounts used this system.
Old cine lenses usually have a base screw mount that can be adapted to most cine mounts. For this lens it is specifically, measured from the male thread, 2 inch x 40 TPI.
Since the aperture and focus mechanism were very hard to turn, I had to disassemble the whole lens. It took some time and I worked slowly to avoid damaging anything. I took a picture of where the helicoid detached so I would be able to screw the multi-start threads back together after cleaning.
I degreased all the moving parts with isopropyl alcohol. Then I used synthetic helicoid lube from Polar Bear Camera, which made the focus and aperture run smoothly again.
After a lot of elbow grease, a ton of q-tips and different chemicals, the lens turned out really well compared to how I found it. There is some paint loss, but that adds to the charm.
Adaption
Adapting old lenses has always been my favorite part of using them. There’s something very rewarding about finding a way to adapt rare mounts.
It always starts with a lot of measuring and freelensing to get a general idea of the flange range distance, and to figure out which mount is best to adapt to. I usually adapt either directly to Sony E-mount, Fujifilm GFX or Leica Screw Mount.
Initially I adapted it pretty rudimentally to GFX with one 3D printed part that was press fitted to the back of the lens. This part held an M52 to M42 step-up ring, which in turn let me attach an M42 focusing helicoid and any mount of my choosing.
All of the shots in this review are made with this adapter, using the Fujifilm GFX 50S and the whole sensor.
The back focal distance is approximately 34.83mm, which is a bit longer than the main competitor, the Biotar 5cm f/1.4 (approx. 30.59mm) from 1927 or 1928. With this added back focal distance it is fully possible to adapt the Kino-Plasmat to Leica Thread Mount with coupling. Front element of the Kino Plasmat 50/1.5 is approx. 31mm and back element is approx. 25.7mm, while the front element of the first Biotar 50/1.4 is 35.4mm, while the back element is 26.3mm.
This is my ultimate plan. I want to learn all I can about Leica coupling, and this is definitely the hardest adaptation to do, because you need extreme precision both for infinity focus and rangefinder coupling.
From what I’ve read, the Leica coupling was originally made for their 50mm lenses, which in reality are 51.6mm. From then on, all Leica lenses with coupling have to follow this cam movement, which is not easy to calculate.
If your lens is above or below 51.6mm, you have to either use two helicoidal movements, one for the actual focusing of the lens and another for the cam movement, or make a cam profile that compensates for the longer or shorter movement of the lens while focusing.
That means the cam is not perfectly flat. It must have either an incline or a decline, which also means the cam has to rotate. If it is static and only moves up and down, this method is impossible.
Ideally I want a design that lets you detach the coupling when you don’t need it. The coupling will reduce the image circle, because the cam cylinder is pretty narrow, as it originally needed to fit inside a female M39 thread. Additionally, the coupling mechanism extends beyond the Leica Screw Mount.
I’ll most likely write a second post when the Leica conversion is finished.
Optical Lens Design
The Kino-Plasmat f/2 and f/1.5 are constructed with 6 elements in 4 groups. That sounds like a double gauss, but this lens design is completely different.
The original patent for the Kino-Plasmat f/2 lens states the lens design from front to back as:
- 1st group: biconvex, negative meniscus
- 2nd group: negative meniscus
- 3rd group: negative meniscus
- 4th group: negative meniscus, biconvex
When cleaning the lens I noticed that the Kino-Plasmat f/1.5 is more like this:
- 1st group: biconvex, plano-concave
- 2nd group: negative meniscus
- 3rd group: negative meniscus
- 4th group: plano-concave, biconvex
What differs from the patent is that the two glued groups have a flat plano-concave element. I’m not sure why this was done, and I wonder if the original f/2 version is also flat or curved.
Here is a small estimated possible coverage overview for different Kino-Plasmat focal lengths. The Kino-Plasmat 75mm f/1.5 probably can’t be coupled to Leica, as the cam will likely obstruct the image circle.
- Kino-Plasmat 12.5mm f/1.5 on 16mm film: 43mm f/4.8
- Kino-Plasmat 15mm f/1.5 on Super 16mm film: 45mm f/4.2
- Kino-Plasmat 20mm f/1.5 on MFT, confirmed: 40mm f/3.0
- Kino-Plasmat 25mm f/1.5 on APS-C, confirmed: 36mm f/2.2
- Kino-Plasmat 35mm f/1.5 on full frame, confirmed: 35mm f/1.5
- Kino-Plasmat 42mm f/1.5 on full frame, confirmed: 42mm f/1.5
- Kino-Plasmat 50mm f/1.5 on GFX, confirmed: 41mm f/1.2
- Kino-Plasmat 75mm f/1.5 on 4×6.5cm: 43mm f/0.9
- Kino-Plasmat 90mm f/1.5 on 6x9cm, confirmed: 39mm f/0.6
A 1928 German transmission test found the Kino-Plasmat 50mm f/1.5 sample to have an effective focal length of 52mm, with photographic effective speeds between about T2.2 and T2.8 depending on plate and filter sensitivity. The old table also mentions the bare mechanical opening to be f/1.76, I measured the diameter of the opening of the mechanical aperture too, and it was 27.9mm, so that is correct. But this is not the actual entrance pupil, which is observed from the front with all the optical elements installed, which in this case will magnify the aperture hole, making it an f/1.5 lens. In modern use, its actual T-stop would need to be measured again with modern spectral standards, but the table strongly suggests it loses a lot of light internally and is not a true T1.5 lens. I crudely tried to estimate the T-stop of the Kino Plasmat f/1.5 lens with comparing a lens I own that have a known T-stop value, then compare it to this Kino-Plasmat lens, and doing some math on a modern sensor it seems like the actual T-stop is more around T1.8 or T1.9. This results in around 31-38% light loss. This is usually caused by uncoated air-glass surfaces causing reflection losses.
Use the slider to change f-stops. Focus set at 0.6m for close up, and infinity.
Results: f/2.8-4 seems to be the sharpest. There is a window in the background that is very bright, which result in some kind of lens flare in the middle that becomes quite distracting, starting from f/4-5.6 and get gradually worse to f/16. I’m not sure what causes this, non-coated issue? internal reflections either from the optics alone or the aperture blades itself?
Image and Lens Characteristics
Just because the image circle covers GFX doesn’t mean the whole image circle is corrected. So it’s a bit unfair to judge the lens when pushing it far beyond the format it was intended for, which was 35mm Academy. That format is close to modern Super35 or APS-C.
Nonetheless, I chose to use my Fujifilm GFX sensor when testing the lens because I like to push lenses as far as they can go. You can see from the illustration what the different formats would cover, and the 35mm Academy crop naturally shows far fewer imperfections.
On GFX, the lens behaves like it has a sharp central area, a curved mid-field and a collapsing outer image circle.
This is caused by a couple of things. One is strong field curvature, which makes the bokeh swirl more and more the further away from the center of the image circle you go. There is also some coma distortion toward the edge of the image circle.
I have to wonder if the image circle was designed to be this large to reduce distortions on smaller formats like 35mm Academy.
Fully open, the lens is never 100% sharp. If you pixel peep you will see some blur over the entire frame. This also creates a beautiful warm glow around highlights, which is especially pleasant for portraiture.
Stopping the lens down removes most of the distortions, glow and blur, and the lens becomes more or less indistinguishable from other lenses. There is also a tiny bit of pincushion distortion, which is the opposite of barrel distortion. This can easily be adjusted in photo editing software.
Lastly there is slight vignetting on GFX. Not as much as I expected, but when shooting towards the sun it becomes more visible.
Summary
In many ways the Kino-Plasmat 2 inch f/1.5 looks similar to the early 1927 to 1928 CZJ Biotar 5cm f/1.4, which would have been a direct competitor in lens speed in the late 1920s and early 1930s. Both have some swirly bokeh, both have a hard time being 100% sharp wide open, and both show what happens when 1920s optics are pushed very far.
Because I have both lenses, I want to compare them directly in the future.
In all, the Kino-Plasmat 2 inch f/1.5 clearly shows the limits of very early high speed optics. It’s not exceptionally sharp, but it’s not worse than other early high speed lenses like the Biotar 5cm f/1.4.
The Astro Tachar 50mm f/1.8 and Ernostar f/1.8 were also made around this time. They were simpler optical designs, at least the Tachar, and not as fast as f/1.4 or f/1.5, so they are hard to compare directly. I would assume they perform around the same when stopped down to f/1.8. From my personal experience, the Ernostar 8.5cm f/1.8 is one of the sharpest fast lenses I’ve tried from this period. The Ernemann Kinostigmat f/2, a Petzval design, is also very sharp, but only in the center.
But for us who love vintage lenses, caring about sharpness becomes much less important. If we wanted sharp, we’d go for modern 20 element, super coated lenses instead.
The Kino-Plasmat 50mm f/1.5 is special for different reasons. It is rare, it comes from a respected optical company, it has an interesting history of innovation and world records, and the images it creates are unique and filled with character.
One of the biggest surprises was the image circle being so much bigger than the direct competitor, the Biotar 5cm f/1.4. I’ll use the Kino-Plasmat much more in the future just because of this alone.
Pros
- Rare and unique optical design
- Distinct image with tons of character
- Large image circle
- Solid build
- Easy maintenance
Cons
- Strong field curvature which produces unsharp corners
- Not generally sharp at f/1.5
- Contrast loss in direct sunlight due to lack of coating
Sources:
- Der Kinematograph (January 1926)
- Lichtbildkunde Volume 1 (1927)
- English Mechanic and World of Science (1926)
- VDI : zeitschrift des Vereines Deutscher Ingenieure (1928)
- Kino Plasmat f/2 patent (DRP 401630)
- US PAT 1833593 (Rapid Plasmat f/1 patent)
- Meyer Plasmat brochure (1938)
- Kodacolor (Wikipedia.org)
- Central-Zeitung für Optik und Mechanik (1926)
- Photo-Ciné (1927) (cineressources.net)
- Photo-china.net
- Kinotechnisches Jahrbuch 1925-26
- Geofysiske publikasjoner (1935)
- Publications of the National Research Council of Canada (1931)
- Investigations of the Aurora Borealis at Nordlys Observatoriet Tromsø 1929-1930
- The handbook of motion picture photography (1927)
- Der Kinematograph (May 1924)
- optik-verlag.com
A truly excellent writeup with lots of well-researched, unique and in-depth information and outstanding presentation, very adaquate for such an iconic lens (series). And of course also great looking and meaningful sample shots showing the capabilities of this wonderful lens. Great work, highly appreciated!