January 2023 | The Robot Royal 24: a clockwork, square format 35mm film camera
Robot Camera Company was started in the 1930’s after a watchmaker named Heinz Kilfitt designed and developed a clockwork 35mm square format compact camera which had inherently 50% increased film economy and could shoot continuously on a spring driven motor failed to sell his design to the big Kodak and Agfa of the day. Instead the design was sold to Hans Berning who set up the Otto Berning Firm.
I made a YouTube video about using this camera which I encourage you to check out if you are interested in some hands on information and experience. For this article I will dive deeper into the technical and historical things that I have been able to find.
The Otto Berning Firm was granted its first Robot patent in 1934, and soon were producing spring motor driven compact cameras without rangefinders and short focal length lenses with greater depth of field.
The camera that I have is the Robot Royal 24 Mod III which was made between 1953 and 1957 in Germany in a run of about 11,500 production units. It was also accompanied by “36” and “18” variants. The “36” shoots a traditional 24mm x 36mm negative familiar to anyone who has shot 35mm film. The “18” variant is an exact half frame, being 24mm x 18mm in portrait orientation. And the “24” variant that I have shoots a rather unique 24mm x 24mm square negative.
In addition to the unique-to-35mm 1:1 aspect ratio this camera is built around a very wild spring driven mechanical motor drive that allows for continuous shooting in a stills camera from the 1950’s!
The Robot camera company is known for their unique clockwork solution to a fully mechanical camera that shoots continuously. One complete winding of the mainspring of my Robot Royal 24 yields ~25 uninterrupted frames from the clockwork motor drive. Robot advertisements from the day claim that you can shoot at a blazing 8 frames per second! I think this is likely under ideal freshly lubricated circumstances with a brand new camera though, as my 65 year old camera yields about 6 fps at 1/500th and about 4fps at 1/25th of a second shutter speed.
I did take apart, clean, and adjust all three lenses for this camera when I got them and I also cleaned and re-aligned the rangefinder and surrounding viewfinder but I did not trust myself to successfully take apart, clean and most importantly put back together the spring motor lower half of this camera so I can’t say how old the lubrication in my camera is or when it was last serviced.
In the year I write this, 2023, film prices have risen dramatically in the last two years (for good reasons, hopefully) and those of us who got into or back into film photography between say 2015 and 2019 are really feeling the double digit annual price increases recently. A benefit of this camera is that it shoots 24mm x 24mm squares rather than the standard 24mm x 36mm rectangles we are so used to in 35mm. That means that this square frame Robot yields 50% more images than a normal 35mm camera, or ~54 shots from a roll that would normally yield 36.
Personally I really wish there were more square format 35mm cameras around. It is an aspect ration that I really connect with and which makes sense to me when composing or thinking of images in my head. Square 1:1 is the native aspect ratio for many very successful medium format systems such as Hasselbald, Rolleiflex, and others but like I mentioned above the only competitor to the Robot Royal that I could find was the Zeiss Tenax II.
Loading film takes more time than most other 35mm cameras. This is because of a requisite proprietary three piece takeup spool. The camera cannot be used without this takeup spool. While it is slower than most other 35mm cameras, it is not inhibitive, and it is physical film of course and if I absolutely have to have a specific picture of something instantly my phone is always with me. (I show this process several times in the youtube video linked above if you want to see it!)
Technically the take-up spool is light tight, with a swing arm that the film door actually presess on to open the take up cassette and prevent the film from being pulled through felt more roughly when shooting in continuous mode. It also means that if you open the back of the camera at any point, the film that you have already shot is safely protected from the light and you would only lose the unexposed film that is between the two cassettes.
One advertisement from the 1950’s for Robot said that I read said that one could take a roll of film out early, cut it, and send it for processing sooner, or that one could change film mid-roll and only lose a couple of frames. Personally even if I had multiple takeup spools this process sounds like more of a headache than it is worth.
The film counter needs to be reset manually after loading film each time, this done by depressing a small button on the top plate and rotating a wheel on the back of the camera.
Schneider Kreuznach made several lenses for the Robot camera system in the proprietary bayonet mount from 30mm up to 200mm.
There are no framelines in the viewfinder of this camera, and the viewfinder at that is on the smaller side. I have a Robot Universal Finder which rotates to increase or decrease magnification of view from 30mm to 75mm which is a nice accessory but I have also found that the framline-less viewfinder roughly correlates to about 40mm so with the 40mm lens I frequently use that rather than the accessory finder. It is less accurate but only slightly so I just keep that in mind when composing.
The lenses focus and are rangefinder coupled down to 0.75 meters or 2.5 feet, beating Leica to that minimum coupled focusing distance for rangefinder lenses by about a decade!
The difference between 1 meter and 0.75 meters may seem small but I find that it makes a big difference when you are sitting across someone at a table, or are in the close quarters generally. I have some Fuji rangefinder lenses from the 1950’s in Leica Thread Mount which I love and use on my M3 but if I am out to dinner with someone I do feel like I must lean back slightly to take their picture.
All this to say, I really like that these Schneider lenses for the Robot focus down to 0.75 meters. I also like that because the composition is a square, I never have to rotate the camera to portrait orientation the way I might with another 35mm camera. I don’t really like 2:3 aspect ratio too much, but I find myself minding it less in portrait orientation, sometimes.
All the lenses use a proprietary bayonet-ish mount that includes a 36mm thread that is cut into thirds around the mount. I was able to get my hands on an adapter step up ring to M39 which is easy to adapt to M mount and so on any mirrorless camera these days. I think I might try and use these lenses on digital for some video but not certain what else. My real aim was to take comparison images on the same high resolution digital sensor to document the lens characteristics which I’ll show here now taken on my 60 megapixel Sigma FP-L (the camera I use for digitizing my film with a macro lens.
I have three lenses for the Robot Royal: 30mm f/3.5 Xenagon, 40mm f/1.9 Xenar and 75mm f/3.8 Tele-Xenar. These digital files are completely unedited, straight out of camera with the same settings applied in camera (click to enlarge). The first three are all shot at the widest open aperture of each of the three lenses:
I noticed that the 40mm and 75mm cover the full 24mm x 36mm sensor well but as you can see the 30mm is meant for the 24x24 square format variant only and thus has a smaller image circle and vignettes heavily on the full frame 24x36 digital sensor. There is some light vignette on the 40mm at f/1.9 on full frame but it goes away even when stopped down just one stop and also means that there is zero vignette on the 24x24 squares from the Robot Royal 24.
My real aim was to take comparison images on the same high resolution digital sensor to document the lens characteristics. You can make up your own mind but I find that the 40mm is the sharpest of my lens copies, even wide open. he 30mm is the softest, even stopping down, but it is also offering a much wider field of view so I don't feel that the lower sharpness detracts from the images with more context included and especially with some grainy black and white film that looks like a charcoal sketch to me. The 75mm is soft wide open at f3.8 but by f5.6 it sharpens up really pleasantly and f5.6/ f8 seem to be the sweet spots for me, with my copy.
As you can see, the image circle of the 30mm lens is quite small and in fact all the way to maximum aperture of f/16 there is still heavy vignetting on full frame. I rather appreciate it on 24x24 though, especially because I find that my eye is not searching for sharpness on the wider angle of view with much more context included. Especially for street photography with some grainy black and white film it reminds me of little charcoal sketches.
The lenses have a frustratingly uncommon 38mm filter thread, for which I could only find a period Robot yellow filter which was really expensive (like $60!). For the same reason I don’t have a lens hood, although there is a period Robot Universal Hood that can work with the range of lenses from 30mm to 75mm but it looks inconvenient to me. Even though they are coated, lens flare is not uncommon especially with the 40mm and 75mm but it isn’t very bad and I tend to appreciate that aspect about vintage lenses so I am not worried about not having a lens hood. (of course too much of anything is rarely great, and as you can see in the third example below it is definitely possible to blow out an image with flare in direct sun.
Shutter speeds on this camera are represented in the older: 1/10th, 1/25th, 1/50th rather than the more common 1/15th, 1/30th, 1/60th on newer cameras. I don’t treat them any differently however. A nice thing about the rotary shutter system in this camera is that you can sync flash at all speeds, more similar to a leaf shutter than to the curtain shutters many 35mm cameras have. Also like most leaf shutters the Robot has a maximum shutter speed of 1/500th which can sometimes be limiting but just shifts more priority of focus to the other points of the exposure triangle.
The focusing rings on these lenses are not my favorite. They are thin and to me do not feel intuitive to grab. They are certainly usable just fine and after I re-greased my lenses they all focus very smoothly but they are not as nice as other focusing rings that my other old rangefinder lenses from Leica and Fuji have.
The lenses do however have a very clever color scale hyperfocal distance tool that makes finding the hyperfocal distance of various apertures very fast, easy, and intuitive. Every other aperture, so f4, f8, and f16 are all assigned a color. Then on the focusing wheel there is a corresponding dot of the same color. Set the point of focus to that color dot and everything between infinity and the nearer portion indicated by the aperture ring is in focus. On the 40mm for instance at f8 I know that everything from about 10 feet to infinity will be in focus.
I think the construction of the focusing ring and the creative hyperfocal distance scale speak volumes to the intended uses of this camera and also its versatility. You can snap into hyper focal zones and barely lift the camera to your eye while firing a dozen frames in quick succession, but you can just as easily and appropriately take your time to use the accurate rangefinder to find critical focus for a specific shot.
This means I think this camera is uniquely suited to fast action and street photography shots as it is for carrying around as a daily driver with a high capacity of 55 frames and a compact rangefinder design with just as compact yet really superb lenses. The 40mm focal length is somewhat divisive with many people preferring 50 or 35 but to me 40mm gives the best both and I'm always happy to have it on me.
There is no self timer on this camera which makes sense because it would have (I think) likely increased the complexity of the already complex shutter mechanism but would have been really really cool. There is however a little foot that slides out 90 degrees from the baseplate around the tripod socket which lets the camera stand upright on flat surfaces.
Rewinding the film is done by turning the knob on the top left side of the camera to wind it back into the original cassette. There is no flip out arm to assist, so it is very similar to the Leica M3 and earlier rangefinders. You must slide the mode selector switch to the right toward “R” to release the take-up spool and allow it to spring in the opposite direction. It is important to not shoot past 55 frames, because if the shutter mechanism begins but does not finish a complete cycle (on account of the film being finished) it will jam and not allow you to slide the mode switch to “R”.
In addition, the frame counter spins backwards when you rewind the film which is helpful because you can not fully rewind the film into the original cassette on account of the teeth on the take up spool that lock into the sprocket holes. So it is nice to follow the film counter to “0” and be certain your film is fully rewound before opening the film door. The takeup spool and canister are light tight when you open the film door so this also helps: you would only lose the 3-4 frames outside of both the takeup cassette and original film cassette.
It is important not to shoot it past 55 frames because then you cant switch it into the “R” position to rewind the film, which releases the take-up spool letting it spin the opposite direction.
The Frame counter turns backwards which is nice because you will be able to tell when you are back at 0 since you won't be able to wind the film all the way back into the original cassette given the little teeth on the take up spool and you don't want to expose your film by accident.
The shutter sound of the Robot Royal 24 is different from most other shutter sounds you might be familiar with. That is thanks of course to the clockwork mechanics that make this camera come to life. I do a comparison in the YouTube video (here) to my Nikon FM3a and Leica M3 that you can hear for yourself the differences. I think it sounds somewhere in between a rangefinder and an SLR but it also has a much more metallic sound which I find sort of steam-punk-ish and cool.
I also did a brief, very unscientific comparison of the Schneider 40mm 1.9 with yellow filter to my Nikon 50mm 1.2 AIS lens also with yellow filter. It isn’t a fair comparison because the 50mm has a faster maximum aperture and is also slightly tighter but just to give a brief idea of how the character of the vintage Schneider compares to modern glass with modern coatings.
Schneider 40mm 1.9 lens at f/1.9
Nikon 50mm 1.2 AIS lens at f/2.0
The 40mm was shot at f1.9 and the 50mm was shot at f2.0 and they were shot on the same roll of film which was CatLabs X Film 320 Pro pushed to 800 developed by hand in Rodinal. The Nikon is sharper to my eye, thanks in part to being stopped down, but also exhibits better micro contrast. The Schneider still looks plenty sharp to me though even at its widest open aperture but I also really like the falloff of this lens, personally.
I think the Robot Camera Company was ahead of its time in many ways such as the combined rangefinder/viewfinder, rangefinder coupled focusing to 0.75 meters, and of course the defining clockwork shutter/advance mechanism. Being based in Germany after WWII presented its own challenges and burgeoning international competition in the space of consumer cameras and also the very low cross compatibility of the Robot Camera system pieces (the lens mount is proprietary, the filters are extremely unique, the take-up spools are proprietary all led to Robot Camera pivoting more heavily into the surveillance side of photography for instance creating film cameras for low speed video monitoring of banks, traffic intersections, and anything you can think of. This market was of course devoured by digital even more quickly perhaps than the consumer camera market but while the Robot Royal series represented some of the last and most advanced consumer cameras they made, Robot did continue to make photographic equipment into the 1990’s including purpose built espionage tools that remind me of old James Bond movies.
One frustration for me is that there are no strap lugs on the ends of the camera to attach a neck strap. I believe that Robot made an ever-ready leather half case that had a neck strap but personally I don’t love the added bulk and I have not found one in a nice condition which I would actually use. I did pick up a wrist strap from Gordy's Camera Straps which screws into the tripod socket on the base of the camera. This works really well and I don’t mind it but I would have preferred the option to use a neck strap.
Being a camera from the 1950’s it should go without saying: there is no light meter built into this camera. I’m used to this with my M3 and my Hasselblad, and I just use my phone or an external one.
This is a camera from the 1950’s and it feels metallic and dense and I like that about it. It makes me think differently about capturing motion because it occupies the space kind of in-between video and still photography. It always makes me think about ways in which I can capture a very specific glimpse of movement, maybe only across three to five 24mm by 24mm frames. I am particularly interested in exploring this idea more deeply and experimenting with different shutter speeds and subject matter.
Typically on my camera copy I get 6 frames per second at 1/500th for 25 frames (about four seconds) or about 4 frames per second at 1/25th of a second shutter for as many frames (about six seconds). I like the idea of maybe chopping together a brief little moment only around 30 seconds but trying to tell a meaningful story in such a short amount of time sounds like a really intriguing challenge.
I’ll certainly make more videos about my exploration of motion with this camera and if you’re interested then definitely check out the one I already made going hands on and demonstrating its use: here!.
