Aapo Lettinen

I got the phase locking working with my prototype. It still needs fine tuning and I will change the phase locking algorithm to get better accuracy and to get it working correctly under 16fps (160Hz). The prototype motor has 10-slot encoder so the frequency is 10 times the fps. So 16fps = 160Hz, 25fps = 250Hz and so on. Look at the lower frequency rating on the "Average", that is the median motor running rate. The upper frequency is the crystal reference frequency coming from the oscillator. The whole motor control code is currently running from a single Attiny85 microcontroller. If wanting three digit accuracy I may need to use different system but as you can see this system is already pretty good. I will test this code version next with the motor attached to the actual Kinor16 camera and then I will get to adjust it with actual film load. The motor already reacts to changing dummy loads correctly so I am sure the current version will already work pretty OK with the camera but we'll see. I will probably post a video when starting to work with the full camera + motor setup :)

The pressure plate should push the film against the edges of the gate to get the frame edges flat against the gate. It also needs to support the center of the frame area to keep it at the correct distance so that the center can be focused at the same plane as the frame edges. so the center support is very crucial for image sharpness. But there is a catch. The film does not stay flat on the gate and it may even be beneficial to let it develop a small controlled curve so that it is easier to make the lens's focus curvature flat (it is easier to let the film plane to be a little bit concave than to make it perfectly flat and correct the focus curve in the optics). So the center area of the pressure plate may be machined to slightly lower plane than the areas which push against the frame edges. This is to let the film to develop the tiny amount of concave curve instead of staying perfectly flat. Don't know which cameras do and don't do this correction on the pressure plate areas but it has some benefits so I assume the newer Arri cameras would use it. If the plate surfaces have the correct smooth finish without defects there should be no problem them touching the "picture area" which is the backing of the film and not the actual image

chips can be a problem but scratches rarely show up unless shooting wide angles stopped down. If you have a mount adapter to attach the lens to a still camera it will be very easy to test if the marks will show and if they do, which are the settings to avoid if not wanting them to show in the final image. I have one 10mm /1.8 made for standard16 and it has one single chip mark close to the center of the front lens. Sadly it shows up badly in the image with all settings and cannot be masked with black etc. or repaired so I may need to get a new lens. It looks like there would be a water droplet on the center of front lens all the time and it shows in all lighting conditions. So it is possible that the marks limits the lens's use but it needs to be tested with a camera to know

just a little follow up with the K2 electric/crystal motor modifications stuff. I had time to check it again and it does not seem to make much sense to do a crystal modification for this type of camera. It is possible of course but the main thing is that the camera body and mechanics are pretty restrictive and the huge amount of gears make lots of noise which would need to be blimped. the viewfinder is not very good for this type of stuff either. And one would want a video assist too of course which would complicate it even more. Larger mags would also be a huge benefit. It would still need to be affordable but that would not be possible because there is so much work to modify it to meet all the expectations. There is one good possibility though if someone has any interest in it. One could take the film movement+mirror+gate assembly and the ground glass assembly and part of the viewfinder optics and the main sprocket drive and some other parts out of the K2 or K3 camera and make a completely new camera body where these would be installed. So one would just scrap the outer shell of the Krasnogorsk camera and build a new camera using some of the inner parts from the K-camera. This way one would get room for the motor and the video tap, one could make a orientable viewfinder for it and use separate larger mags with it and one could also install a more practical lens mount to it. And one could use a belt drive between some of the components to get rid of the large number of gears. And one could make it much more silent to begin with. I don't know if this makes any sense in the end but it would definitely be possible because almost all the precision parts could be taken from the Krasnogorsk camera and only things like viewfinder tubes and the camera housing etc. would need to be manufactured which does not require special tools or that much expertise (just lots and lots of time). This option would only make sense as a DIY pastime project for camera enthusiasts but could be pretty useful and affordable if one does not count his/her own working hours. The final camera should be usable in indie films if one makes it silent enough. If someone would like to try this type of "frankencamera" Krasnogorsk project we can draft something out here and make a project out of it :) I should be able to provide an OK priced simple crystal sync system for this type of camera later this year if someone would be interested. As I said one would need to build one's own camera body for the project to make financially any sense but this type of camera could work as a "semi-opensource" project or something :)

My Kinor16cx-2m and Konvas projects are continuing in this thread: I will probably do most of my crystal sync related updates there for the next couple of months because I will mostly work on the Kinor16 motor prototype. I will also post videos every now and then ?

It seems that the Konvas motor project may be delayed a little because there is not much interest for it. At the moment I am developing phase locking functions using the Kinor16cx-2m motor and my prototype crystal oscillator as a testing platform. I am in the first stages of tuning the phase locking code so it does not work correctly yet but you can see here how I am testing these systems and what it looks like at this stage. I am using Attiny85 microcontrollers for these tests because they are fast to program with my tools and I have lots of them. I may migrate the code to other microcontrollers later when it is finished. Probably doing more videos also. There is info in the video description if someone is interested ? https://www.youtube.com/watch?v=AGd8g07A4Kk

you can also use a blacked out cardboard box if not having anything better. If having a very large changing bag you could just use it over the box. Or black it out with black cloth or plastic on all sides and use sleeves on one side to handle the film

It seems that I will try this project this Autumn. No one here has been interested in this type of system so I will probably just do it for my own camera and when getting something ready I will post the results here :) I am planning making it according to the following specs if it seems practical. If I am doing the system just for my own camera it is easy to do anything I want :) - from 11 to 20 preset crystal speeds, OR a adjustable crystal speed generator with small increments so that I can set any crystal speed from the specified fps range. - a good display to see the settings - works on 12V batteries via standard 4-pin XLR - control electronics are in a small external aluminium box which has attachment points to be mounted on the side or on the top of the camera. Box is connected to the actual motor via cable which transfers the power and the encoder signals. - maybe some kind of onboard battery which attaches to the side of the control box. Needs to be Lithium so will need to see if it's practical or not to make.

Oh you meant like 30 years ago, not today. The typo was misleading :)

that meaning ANY film stock... the stills films too. The reason why film is made in wide master rolls is because the edges of the roll are always uneven and have to be cut out. So there will be less waste if one always coats a very wide roll and then just slits it down to smaller formats. That way much larger percent of the coated material is good quality and usable.

film stock is made in wide master rolls and then cut to the desired widths which fit different cameras. And then perforated and wound up in small rolls which the cameras can use. So theoretically any film stock could be used in a movie camera as long as the antistatic characteristics and anti halation are good enough for that use. If that's the case, one only needs to slit it to the desired format width and perforate it so that it would work in the camera (with the possible need to fine tune the camera before use of course). All the film manufacturing companies may not have tools or financial interest to make their products available in 65mm format (lacking the perforating tools) but if you can get the stuff they make to slit down and perforated to the specs elsewhere there is no reason why it would not work. As long as the company agrees to sell you the raw material in suitable sizes which can be used for this work. Probably you could get most of the currently available film stocks to work in a 65mm camera if you are ready to pay enough for the companies to sell you a master roll and get it slit down and perforated. Just needs lots of financial resources and a real commercial use for the stock to make it possible.

The Film Photography Project seems to have some b/w and colour negative stocks available in 2x8mm format though. Maybe it is just more practical to concentrate on the cameras first and then use whatever stock is available locally. I might want to try the Super8 adaptation by myself sometime, I have some Soviet 2x8mm cameras which could be sacrificed and they have so simple film path that it cannot be that much work to adapt them with proper tools. (much easier than to order some color neg special stocks from the other side of the globe just to be able to shoot anything with the camera...)

I asked from Filmotec and Foma about the 2x8mm perforating options. Like I guessed, it is not possible to re-perforate already perforated film by adding more perforations to the space between perfs. Filmotec should be able to arrange some perforation services for 8mm but it needs unperforated raw material and is most practical for Super8 as I understood. I also asked if Foma would be interested in making some of their negative stocks in 2x8mm format but there is not enough demand for this type of stocks to make it viable. So it seems that either Wittner or Filmotec would be the places who could arrange negative stock batches for 2x8mm and unperforated raw stock would be needed. (probably it would be possible to slit 2x8mm stuff from standard 35mm Vision3 stock I believe but that does not make economically any sense. For black and white stocks it could be and option though if someone would be interested in shooting stuff like Fomapan b/w negative films in 8mm format and there would be enough interest so that a large perforating batch could be ordered). One thing which came into mind is though that would it be just much more easier to adapt a 2x8mm camera to shoot normal 8mm wide Super8 film? Then one could just take Vision3 negative from one of those flimsy Kodak Super8 cassettes, load it to a spool and shoot with your camera. Stock would be available anywhere and the amount of work would be pretty trivial if the end results would be crisp and stable when getting rid of the plastic cassette system. Maybe Simon could arrange something like this? adapting for example a Bolex H8 to use single width Super8 film.

Hi you all! I have an old Bolex H16RX from 1957, it is the first RX model ofter referred as the "RX0". Which type of electric motors originally fit to this type of camera, I might be interested in purchasing a motor later this year? There is lots of motors which fit the newer models but I am unsure which ones would work correctly with the old model camera. It would be nice to shoot sync music video stuff with the camera because the C-mount is pretty versatile and I have good lenses for it. I thought I could purchase one or two cheap motors and repair them by myself and maybe add my own crystal sync system to it if it seems practical.

Hi you all ? You may have noticed that I have lots of different camera motor related projects going on.... A forum member asked help on another thread for DIY converting a Cameflex rheostat motor for single speed 25fps crystal sync but he chose to attempt brushless motor route instead because it is much simpler to do. I however already checked the encoder placement possibilities briefly for him and much later though maybe I could attempt this conversion by myself (even though I initially thought it would be unnecessary for me because I will use 16mm cameras for sync sound. But then I realised that I will still want to use the Cameflex for MOS night shooting under streetlights because it has 180° shutter possibility. And so it could be useful for me if the camera would have the 24 and 25fps crystal speeds because it is much easier to haul the rheostat motor and small external box around than to use the large 230v mains operated sync motor and inverter just to be able to shoot under flickering lights.) How many of you actually shoot with a Cameflex nowadays? Would anyone need this type of conversion and how many would actually order it if it were available? It is generally not practical to modify only a total of one single motor or two motors for one's own use. There is significant amount of work on designing the speed control system and it needs to be extensively tested as well. And it takes lots of time and resources. So I think this type of modification would be useful and fully possible but I would only be interested attempting it if there would be at least four or five people who would order the conversion. I would also need to know beforehand what is the maximum price for the work per motor and what would be the most needed features, only then it would be possible to design the system in the first place. I am talking about converting this style of "Type 24" motor which I happen to have two working ones so I could use one of them for tests if there is enough interest for this mod. I quickly drafted that the system could be something like this: - an external control box where the control electronics are. The speed sensor is installed in the motor itself. Some kind of cable connects the two together. - real crystal sync with at least two crystal speeds. Plus a simple variable speed function which allows speed ramps. So I would add at least two speeds and the varispeed function. - more crystal speeds are possible, it may raise the price though. A rotary switch would be the easiest way to select the speed with minimal parts so I would prefer using it for speed selecting. - some kind of display is possible. it is useful with the variable speed if wanting to set a custom MOS speed. Display functions take lots of work to code so it will add to the price of the system. - with current technology it is possible to generate weird off-standard crystal sync frequencies easily. There is some limitations depending on what exact frequency is needed (how accurately it is mathematically possible to divide the original crystal frequency to the desired final frequency) . But any frequencies can usually be divided with at least two decimal accuracy, often better. - Battery type and voltage?? I would personally use my own camera with 12v batteries after the conversion so I would add voltage regulation in any case. So it would be possible to design a system which runs on V-lock batteries or similar style batteries. So a 4-pin XLR at least but what more? a v-lock adapter to the back of the control box?

by my experience, wireless technology pretty much IS garbage. this includes both wireless video and wireless audio as well as most other types of wireless data like computer and cellphone related stuff. Maybe it is a bit subjective and maybe I have just had bad luck with all the wireless gear I've ever used (or maybe I am myself generating so much electromagnetic interference that the devices just freak out :D ) Paying 2000 or 5000 or 10 000 for a wireless mic kit does not make it "excellent working" and "absolutely reliable". For example I had some bad experiences with wireless lavalier kits costing from 2.5K to 5K a piece

I think anything shot in the Soviet Union would apply to this category as well

by my opinion, there is really no reason to cheap on sound equipment. Most of it lasts forever even in professional use and the technology does not get old so you can use the gear until it finally gives up after 20 or 30 years of use. the exception is wireless technology which tends to be garbage in all cases and may need to be updated regularly especially if the regulations change (they have banned frequencies couple of times which makes using old wireless gear illegal and everything had to be upgraded to newer versions. this is very expensive if you have multiple wireless sets). Cables and connectors will break too as well as the antennas of wireless gear. But it is nothing like camera bodies which are like a stick of butter left in the sun, gets old in the blink of an eye and you'll need to buy a new one. Any other gear may break as well if you let someone borrow it or rent it but that applies to pretty much every other kind of gear as well....

there was some interest in having custom speed crystal motor for the 1M and 2M cameras. So I will most likely check this option soon ? if someone else is interested in 1M and 2M custom speed motors, you can let me know by PM. I will make some tests and prototypes in the next two months and should have some possible options available then. At the moment I am using Kinor16CX-2M motor as a testing platform for my crystal sync camera controllers (I have two of these motors so it was the easiest one for my tests, just a coincidence) . So these Kinor motors will be easy to modify as well if needed (though Olex already has a very well working crystal motor for the Kinor16 so probably it is best to use Olex's motor with the Kinors unless one needs something really special like a one-off modification with lots of custom features) I keep you updated when I have a working prototype to show ? Please note that this thread is specific to Soviet/Russian cinema cameras and making motor modifications for them. If there is more general questions or ideas about making stuff for other type of cameras, please start a new thread in the camera subsection specific to that camera model or a more generalised thread can be created in the "Camera Accessories and Tools" subsection of the forum.

well, there might be issues of the lens's back part fitting well enough inside the adapter. This has to be actually tested to ensure compatibility, there is no way to know any other way. The adapter and lens inner geometry may be such that it either works or not. If it does not, it is probably going to be way off, like the lens not being able to screw in even half of the required depth. But you should really just purchase a adapter and test this if you already have the lens. The adapters are cheap and you will have other uses for it even if it does not work with that particular lens. As for using heavier lenses with a Bolex, yes you will definitely need some support for it. For the lighter ones it may be enough that one screws in the special support plug which locks the bottom corner lens port of the turret to the camera body. For larger lenses additional support may be necessary. Don't use zoom lenses without at least having that turret locking screw in place, the turret will not stay at correct alignment and the FFD will change continuously when a gap develops between the turret and the camera body because of the strain.

sounds interesting! and should be relatively easy to do with minimal parts. I don't have much experience with brushless motors but I can help with the mechanical ideas in case you need them :) Do you have access to machining tools or have a friend who has the tools (typically at least a metal lathe and milling machine with dividing head), that would help a lot when adapting a suitable motor for the camera? I understood you will like use the original angle gears from the Cameflex motor and just replace the top assembly which has the motor itself and the rheostat controller. But it might be worth investigating if it would make sense to just make a completely new assembly which has similar axle connection than the original motor. Should not be complicated for someone with the necessary tools and some time. Depending on the motor you want to use, this could give more freedom on the designing process. There should be lots of info about Arduino controlled brushless motors, they are used in robotics etc which is one of the primary use of Arduinos

the Pocket4K with a speedbooster or the 6K. Or the GH5 or the GH5s with a speedbooster. You can use cheaper Chinese speedboosters if the Metabones ones are too expensive for your use. I use the Zhongyi Lens Turbo II which is pretty OK quality and costs 1/4th or 1/5th of the Metabones price (the Metabones's are useful if you need electric lens connections and adjustments. Otherwise a "dumb" adapter should do)

I had some connection issues with the LED at times, it may be that it had slight flicker as well. I am using GH4 as a pickup camera with 1/4000 shutter and shooting full res raw stills. appropriate macro setup to get the full academy frame plus some borders in the shot. I have a optical trigger which drives a relay which connects the wires on a wired remote control cable which triggers the camera. The problem with the timing seems to be that the relay itself has some slightly varying latency which causes the framing to differ a little from frame to frame especially when the scanner speed varies slightly. So I will need to change the relay system to a transistor based one which has less latency but is more complicated to make (I was using the relay only because it is very very simple system and thus practical for the first prototype). I am not able to get the perforations in the frame with the current setup, would need to machine a completely new gate for that. The current one has pieces from Konvas camera gate and magazine but they don't allow enough modification. I used AE's tools for this test but I would really need the perforations to show up to be able to stabilise this much jitter without the manual correction stage. Some very good film restoration program might understand that the image can jump up and down even 1/5th of its height between frames...but the basic tools seem to be unable to cope with that. The film is pulled through the system at slow speed and the optical trigger takes one image for every frame. It works, yes, but needs to be refined to get better accuracy on trigger timing. Too fast scanning speed also causes rolling shutter issues to the image, this has lots to do with the current film track. I will add three rollers more to counter the friction variations which cause the film to move irregularly at times with the current prototype. I will probably do a separate system later which uses intermittent mechanism to move the film. Register pins might be possible too as well as a faster scanning rate. These systems are mainly practical for film tests and that is why I am developing them in the first place... to run small 50 or 100ft rolls of home developed film through to check grain textures and contrast and similar stuff. Probably for arts projects too but for larger scale stuff it is still more practical to use pro lab and scanning services ? 1st prototype after all. We'll see how it goes ?

it is a 20w power power LED similar style to these ones and it's diffused with multiple layers of 250 gel. I attached the LED to a old GPU heatsink so it can be on for hours without overheating. that 20w is just barely enough for this type of scanning (takeup macro setup at about F4/5.6 split when I would like to get it to about F8 )and I will need to update it to at least 50w or preferably a 100w later. The stability is more urgent issue now because it is very time consuming to post process the material. I need to first manually stabilise every single frame vertically before any kind of automatic stabilisation can be added... I tested multiple approaches but the vertical jitter is just too much for available stabilisation tools so I first need to manually correct the framing frame by frame and then the automated stabilising and rolling shutter correction can be added. The system is a slow continuous motion scanner with speed of about 1 fps maximum. One of the reasons why the vertical stability is so bad is that I have some latency on the camera shutter trigger system and will need to update it to reduce timing variances between trigger mark and actual shutter release

I will need to make some additional rollers too, the design will need some more of them to be smoother. I am doing the rollers by myself too ?