Aapo Lettinen

PM sent.

Nice to hear that people love to still use the Krasnogorsk cameras! I kind of abandoned all the Krasnogorsk crystal motor designs because it is too much mechanical work to adapt the electric motor to work with the cameras. Additionally the cameras need a complete overhaul to be able to work with any electric motor system and even if serviced, they are still mechanically unsuitable for running very large amounts of film through (that is just my opinion but for example the bearings of the camera need constant care if you are intending to shoot thousands of feets of film with it in a short period of time like would happen if shooting for example a feature film with it). So the combination of large amount of mechanical work + the camera body being not very optimal to be used for filming extensive film amounts by my opinion + the relatively small profit one could possibly make modifying these compared to the large amount of work it would require.... that is why I decided it is not worth it financially to modify these cameras. Maybe in a country where the work hours cost less than here (China, India, Russia, etc.) . However if you are able to do the mechanical parts of the modification by yourself it would be possible to adapt some of my existing crystal sync designs to work with the camera. basically meaning that a suitable motor and speed "tachometer" encoder design would be chosen and you would handle all the mechanical stuff by yourself, I would just provide complete control electronics for the camera according to the specs. The stuff I need to know is what kind of encoder sensor the system uses and how many pulses that encoder provides per one exposed film frame (taking into account all the possible gear ratios between the motor and the film movement, the encoder slot number, etc.). and what kind of motor it uses (brushed, brushless, the exact specs of the motor, operating voltage etc.) and the battery options you are going to use with the system. It is a bit easier to adapt a brushed motor to work with the camera because there is more suitable motor options then. Most of the brushless options I have found are plain bad for camera use (unsuitable RPM, noisy, bad driver boards, etc. or unsuitable Hall outputs for crystal sync which necessitates still using a separate encoder disc system with the motor which ruins all the benefits of the brushless in the first place) . Let me know if you are interested in adapting the K3 to electric motor use by yourself and would need the complete Crystal electronics for it so that you would only need to handle the mechanical parts of the modification. The complete control electronics would probably be somewhere around 400 or 450 USD I believe depending on what you need (the basic would be a 12-speed crystal sync system with a rotary selector to select different speeds. no display or extra features)

if you want to do pinhole stuff on a PL camera it should be possible to purchase laser cut pinhole plates separately and glue or tape them to inexpensive PL adapters or various types of extension tubes (PL, M42, EF or other). https://www.ebay.com/sch/i.html?_from=R40&_nkw=pinhole+laser&_sacat=0&_sop=15

the physical dimensions of the EF mount prevent installing it inside the PL mount deep enough to enable infinity focusing. If shooting macro stuff, almost anything could be done however. You can for example attach the taking lens to the PL adapter with tape or glue if that is the most practical way to do it. the lens just does not focus very far, probably only to couple of inches or so. You can get cheap macro bellows in M42 mount and attach them to PL camera using a simple and affordable M42 to PL adapter (the RafCamera ones or the Chinese ones for example) . You can use M42 extension tubes in between of the adapter and the bellows if needed. Attaching the Canon mount bellows to the PL adapter should be possible too if using some time and machining it a little bit.

the described job is basically taking the sensor, the physical body and the optical parts from the original F35 and making most if not all of the camera electronics by yourself from ground up. Similarly demanding than purchasing a plain image sensor from Mouser and building your own digital cinema camera from it doing all the control and signal processing electronics and custom software by yourself. This is probably not a good solution for any cinematography related use... just wanted to say that it is possible and how it can roughly be done if one is experienced enough and has tons of spare time for the project. it does not make any financial sense compared to purchasing a used cinema camera or a new mid range movie camera because the amount of work is huge. maybe a youtuber or similar person could make a project out of it... they have lots of spare time and funding available to do things which do not make any financial sense :P if not having the sensor documentation one could maybe probe the sensor outputs with oscilloscope to find out how the timing control and signal outputs of it work. without that information one can't even start working with it.

3ccd tends to have different, more efficient way to handle colour separation (colour-reflecting dicroic coatings instead of traditional substractive filters) so if done well it should be even more efficient than the traditional single-chip system using "normal" filters. I have understood that the A/D conversion is the most challenging part on the CCD cameras. Is that F35 sensor handling anything on chip level or is the conversion external like in the traditional CCD? it should be theoretically possible to hack a sensor if having the documentation for it but it is extremely demanding and time consuming so probably not worth it for that camera, better to purchase a used Alexa instead ( I would assume it would be a 2 year job for a person to do something like this to the F35). If you can get the sensor data efficiently from analog stream to digital format then you can probably do a custom system using powerful fpga's for signal processing. CMOS cameras are easier in this regard because you already have a digital output on the image sensor level so you "only" have to handle the timing control etc. stuff and the very high bitrate data streams coming from the sensor which is a perfect job for a powerful fpga's to do if one has the expertise to custom program them for the job

I would check the camera with a dummy roll of film to hear if there is any problem with the film transport or possible magazines. The lens should be checked to have functional focusing and aperture. the aperture checked for possible oil on the blades (one can manage with oily iris on a lens but it can show in reflections pretty easily so one should expect more flaring and uglier flares then) . If the camera is affordable you should look for stuff which is outright broken or missing or expensive to repair. you may need to arrange a CLA for the camera anyway before you use it for serious filming so if nothing is actually broken and the motor and film transport work and the lens is functioning correctly and not scratched then it should be OK to buy

I would try Resolve for the correction. or if wanting to use fcpx you could maybe make a correction LUT in Resolve for just the flicker removal and import it then to the FCPX and keyframe it there

I think it doesn't make much sense purchasing native Z-mount lenses. I mean, the camera bodies themselves are not very good (I mean they are good for photography purposes but they are not top notch in any way) so it makes no sense to commit to the Z-line of cameras in the long run. In couple of years you will want to switch to another camera line and then you have lots of unusable expensive lenses in your hands which need to get rid of. What DOES make sense is to purchase the older Nikon F mount lenses (pretty much every model which has the mechanical aperture tab on the back of the lens's mount) . They can be adapted to most other cameras and you can use them with the Nikon Z line of cameras too with the Nikon's own adapter and have full electric controls. I am regularly using the kit zoom 24-70/4 with the Z6 when shooting making of stuff but I don't use any other Z-mount lenses or would ever want to purchase them over the NF mount ones

it is pretty random flickering in most cases. you will have to try to keyframe it out the best you can. make a correction node which has just the green channel pulse adjusted out and then enable/disable it when there is a green "flicker" frame keeping it otherwise disabled. check the rgb waveform or parade to find out how much the flicker pulse lifts the green tones and how to reverse its effect. lots of manual work but should make the shot usable and the audience will probably not notice the flicker anymore

I use similar style RC batteries too to power Konvas cameras. They work very well in that application but the cheapest ones have crazy self discharge rates which is why I need to charge them at least couple of days before shooting with the camera or they don't have any charge left for filming. The cells which have higher mAh rating compared to size tend to self discharge faster by my experience and the "overrated" mAh capacity may indicate that the battery is a bit lower quality than the counterparts which use physically similar sized cells with less rated capacity. You did fully charge the batteries before testing them with the camera or were they left charged for longer period and then you tested the camera assuming that the batteries still had the full charge in them? in case of those rc batteries they may have something like half of the charge left if you store them couple of weeks or a month. Can be even almost empty if storing for couple of months and they are bad quality ones

The Cameflex crystal modification project is cancelled because of low interest. I will make the Type24 motor's crystal modification for my own camera in the Summer but it will not be available for sale. This decision is to save developing money and time for other projects.

when optimising the design it was practical to streamline the design in various ways. it enabled adding more speeds at the same time so why not. I haven't built the prototype boards yet to test how the new speed will work with the actual camera but I think it will have the following specs or very close to these. - selectable speeds: 12fps, 16fps, 23.976fps, 24fps, 25fps, 29.98fps - automatic exposure which compensates for the different frame rates. - probably powered by a 9V battery. - availability TBA but I will first make a prototype for my own use which uses external circuit boards and then we can start to discuss if anyone would be interested in ordering the final version. If no one is interested in it, then I am more than happy to use the prototype one for my own documentary projects even if it is the only Leicina 2x8 in the World which has Crystal Sync ?

I have done some experimenting with the Kiev and I think it might be useful if I'll test using a completely new add-on motor with it. Possibly a brushless motor if I'll find a suitable model (just testing some Chinese made ones which could work). The same motor could maybe be used with the Krasnogorsk cameras as well if modifying the output axle etc. connectors. Could be useful I think. I will continue the Kiev project with open schedule. I am working on the Konvas 15EPSS motor system which should be finished in January. will post pics of it then :)

One of the surprising fields which is lacking in the low budget shoots is the use of sandbags on stands and how many are needed for this and that situation. People will of course do what they are told but they may not have a basic hunch of how many bags would be at least good to have if the light is down vs. fully lifted up on the stand and that compared to the possible wind conditions. Generally speaking, people tend to hate carrying heavy objects around so most likely they are using way too few sandbags for the job. Everyone can imagine what could be the problem with that :P

The g&e is a huge grey area in the indie shoots and there is lots of additional risks because people may not be experienced enough or their skills may lack in specific areas which are not apparent to other crew members. Rigging safety is one of these fields and basic electric planning is another. So I would be extremely cautious in situations which involve overhead rigging or enough lights to burn fuses or overload the genny. (because I have seen literally dozens of people who can't count in their head how much wattage one can take out of a certain amperage fuse or have any idea how to rig something properly to the ceiling. Large frames etc. Can be an issue as well. The problem is that they may be confident enough to try. I have seen for example 5k worth of lights plugged to the same household socket which can only supply about 2k)

overscan generally means that you will get the whole frame and a part of the sprocket holes visible and some small portion of the adjacent frames as well. if you want to see the whole sprocket holes (basically the whole width of the film) then it is sometimes called "superoverscan" depending on the place. I have no idea what they mean by "full frame image" but probably it is the whole image area of the frame without much of the borders or sprocket holes visible or them even left out so it is just a little bit cropped full image area. So I believe that they mean it is not cropped to the correct aspect ratio like you do in telecine transfers so you will get the uncropped image area but possibly not the frame borders. thus "full frame". I haven't had anything scanned on 4k Spirit (they only have 2k/hd versions here) but I have been impressed with the quality of the 4k Scanity scans on 35mm. One would need to consider the price-quality ratio when choosing the scanning options so if the Spirit is more affordable then it might make sense to use it even if there is a quality difference (I get stuff scanned on both Scanity and Blackmagic Cintel because the Scanity has better picture quality but the Cintel is half the price per minute of material. I also get stuff best light telecined on Millenium2 in HD because it is affordable and I love how that machine handles the colors)

actually it DOES happen in internal recordings as well sometimes and it will show in the end result. Switching the n-log off does not help the flickering on external recording but in some situation the flickering can happen a bit more often (or so it seems) if you are shooting in cold-ish temperatures like under 10 - 15 Celcius or so

the green flashing/dark tone flickering can happen on all ISO:s. just when you think you have found out what causes it, it will break the pattern and will find a new way to appear when you least expect it. switching any settings does not help and switching the camera off and on again even multiple times does not necessarily help either. removing the battery for 5 minutes does not necessarily help. there is just no logic to it but I am pretty sure it happens on the sensor level because people tell it happens in proresraw recordings as well. Maybe something to do with improper decoupling on sensor connections or something similar? One other reason to avoid the Z6 is that it does not have anywhere near the dynamic range the manufacturer claims it has. In video use it can record about 10 stops of dynamic range maximum. The colors are pretty good and I like the camera in other ways but the ocassional green flashing and the low dynamic range are its drawbacks. It does not do high speeds in uhd either

I believe people often think it just being generic flashing of the very dark tones which can happen multiple times a second in unexpected situations (nothing electrical lighting around, for example shooting in natural light in the middle of the forest) . It is typically on the green channel which shows clearly on the rgb waveforms so it should be called "green flashing" and not just "flickering dark tones". but if you google Nikon Z6 flickering you will surely get lots of results. The camera manufacturer does not know any solution to this problem either so one just seem to need to live with it if it happens every now and then

the Nikon Z6 has the additional issue of having mediocre internal codecs and ocassional green flashing in darkest tones (very well known issue and impossible to resolve in any way other than switching the camera off and hoping that it goes away. there does not seem to be any particular reason why it happens and every time it is triggered by a different variable. it is not very common but tends to happen once on every shooting day so you need to be careful. It can be corrected in post but it is lots of manual work. I have understood that the new models still have the same issue) I think one of the best relatively affordable options for 10bit video in indie films / docs could be the Panasonic S5, the Z-cam E2S6 or the Blackmagic Pocket cameras if you can stand their quirks

I am making a DIY video tap for the camera as well. I always took lots of photos when making tests and modifications and I think it could be interesting for others to see them too :) today I tested some lens possibilities for the video tap and then removed the back control panel of the camera to plan for the new user interface and take measurements I will use this placement for the speed selection switch because it is more room inside the camera on this location compared to the other side of the panel. I will plan how the other controls are placed on the panel but I think I will install a different type of battery voltage meter in place of the original one. We'll see :)

the diode across the motor terminals is commonly called a "flyback diode" and it is always used when driving inductive dc loads to prevent damage to the control electronics. the diode is used to short circuit the reverse current the inductance generates when power is switches off (in case of a PWM driven circuit like a Crystal camera motor, the power is switched off typically about 30 000 times a second)

yes that type of circuit board images can be edited to make printable masks to manufacture more boards. I think I have the same image in my CP16R manual. But that hardware version seems different and the problem with these is specifically that there is lots of different versions and modifications made for these cameras. bridge wires are a usable solution to repair damaged copper tracks on circuit boards if the components themselves are intact. If components are damaged, then at least some of them can be replaced with new similar ones if they are still manufactured or there is NOS parts available (for example CD4020 binary ripple counters are still available today). Some operational amplifiers for example may not be available anymore and the custom hybrid ic's in the latest designs are of course not available. There is however their schematics available in the manuals so one could make similarly functioning new circuit which replaces the custom IC's. At some point it becomes so time consuming and difficult to repair the original design that it is easier to make a completely new one from scratch. The system I am developing for my own camera has all the original electronics removed except the original motor itself. Even the tachometer sensor will be new so I am only using the mechanics of the camera and throwing all the original electronics out.

my CP16R has a hole under the small top plate which reveals the fibre screen through some kind of beamsplitter prism. One can attach a suitable video camera directly there by removing that cover plate and adding suitable optics to the video camera to get the screen image magnified enough and in focus. I am just making a small 1/3" hdmi camera to work in this application. The cover plate had a light sealing gasket which was installed with extremely sticky adhesive and the only way I could get it open was to take the motor side cover off and pressing the top plate from underneath with screwdriver until I got it moving. So it may be more work than just removing the screws holding it down. But if your camera already has the basic splitter like mine has, then installing the actual camera should be easy enough when using enough time to test the relay optics you have available and when machining a suitable holder for the actual video camera