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aapo lettinen

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About aapo lettinen

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  1. Prores export codecs normally come with the Apple Compressor if I remember correctly. So they are not natively installed on all Macs. For reading Prores you don't necessarily need Mac if your edit software can read it (for example Resolve can)
  2. davinci resolve can import prores without problems and it can export it as well if your operating system and installed codecs support it. So your operating system needs to have Prores codecs installed to be able to export them with Resolve. But importing and editing them in the software is possible without the codecs (for example you are able to edit prores files on a Windows computer running Resolve and without the codecs. But exporting prores is not possible on that system. If using a Hackintosh one can have multiple operating systems installed and have Resolve on all of them and share the databases so that one can for example edit the project on Linux or Windows but do the exporting on OSX to be able to export the project to Prores master. ProresRAW is not supported by Resolve at the moment. It is a licensing issue between Apple and Blackmagic... no technical reason but only about the licensing costs being too high for Blackmagic
  3. if the camera was cheap I would personally ask for partial refund like 50% refund and then repair the camera by myself (that is just me, other persons would do differently and I like to open cameras just for fun to see what is inside). If the DIY repair would work well, then I saved lots of money. If it didn't, I still would have 50% of the original sale price to spend on professional repairs.
  4. if the seller gets difficult just use the return options on eBay. Broken/defective or Not as described. Most sellers are helpful and care about their feedback but there is always one or two who just want to take the money and run... If you still want to keep the camera you can ask for partial refund and then get the camera professionally repaired. If the seller does not want it back then they would most likely agree for partial refunds even if the price they get is much lower
  5. Well, I'm sure that most of us could make more money nowadays by manufacturing "key pharmaceutical ingredients" than by making movies :)
  6. I started to design the two speed version for my own use. Very simple system which is a minimum parts design and uses all smd parts to avoid drilling. It has a simple jumper to select between 16 and 24fps and the auto exposure compensates for the speed change. I will post images sometime later when building the new prototype. Will need to test the circuit design with breadboards first to fine tune it 🙂
  7. I am going to build a two-speed version for my own use soon ( 16fps and 24fps) and we can then check again if anyone is interested in these cameras :) Posting sync sound footage out of the camera is not a practical way to determine how it is working. One really sees the functionality of the crystal sync system only by using correct measuring equipment and by comparing the reference crystal signal against the motor speed sensor signal when the camera is running in various conditions. The thing is, I am measuring 1/10th frame differences in speed stability and one can't really see them in the final footage because, well, they are fractions of a frame, not full frame differences. That is why I like to post breadboard tests with the oscilloscope shown instead of making some random film tests which really would not show any difference. To me, eyeballing the sound sync from camera footage is pretty pointless and only wastes time and money but if I am making this type of test at some point then it is of course possible to see the end results :)
  8. To answer the original question I asked when starting this thread: THERE IS NO DEMAND FOR CUSTOM SYNC SOUND MOTORS. or more specifically, there is no demand for any kind of custom sync sound motors which would have any commercial value. These are interesting projects but most people making them seem to be just very interested making them just for the sake of it, OR they are selling other camera repair services and the Crystal Sync motors are just a way to get more customers for them. For these reasons I am only developing stuff for my own use from now on. If the systems happen to be useful for someone else, then it is of course possible to make one or two crystal sync motors for others. But I don't have high hopes on that. Maybe I am just getting tired of the continuous bashing and disinformation and reverse engineering and everything. The original idea was to help people to restore their old non-working cameras to full working condition with updated electronics and everything so that they would have more tools available to shoot great art pieces on film. Maybe I was just too idealistic or something. And I have learned the hard way that it is not the best idea in the world to try to help people all the time. You will just get yourself burned in the process and not getting much in return. There is endless possibilities available but no one wanting to use them. That is how I see it. By all means, let the film die then. Just shoot digital if that is the only medium which is allowed to evolve, the only medium where it is allowed to have new tools and ideas every year and out of the box thinking is encouraged to get new end results. Shooting on film is the thing of the past because no one is willing to let the format evolve to something else which it has never been before but which it very well could be. Basically your own fault then. I think I'm going to continue my ROV project for a while and then shoot some film again. Concentrating on my own projects from now on. Not trying to be some kind of childish hero who would save all the unusable film cameras out there. That was a stupid idea anyway :)
  9. it is mostly the producer's job to rip the script apart if it does not look to work well and something needs to be changed. In small budget stuff where the director is producing by himself it is very challenging because there is no one to criticise the script and thus every weaknesses are left untouched
  10. I think it would probably be easiest for me to convert the variable speed motor using a external control box with the crystal sync electronics inside and possible to arrange different battery options if needed. I was thinking something like a 6-speed small and compact version without display or a larger one which has a display and from 12 to 16 speed presets. Could be an interesting project when I get my Konvas 15EPSS crystal control finished :) making these is pretty time consuming and costs a bit but it is fully possible. I think there is others converting these motors too (not sure) but you can always PM me later if you are interested in modifying the varispeed motor and I can look at it when having time :)
  11. They seem to pop up on ebay every now and then. There seems to be a jensen motor on ebay at the moment but no tobin ones. You can try the forum and also ask the Motion Picture Technology group on facebook, there is surely someone who has spare ones. Btw if you want to convert the constant speed or the varispeed motor to crystal sync sometime later I could be interested investigating the possibilities for that. I am sure that there is others who already have working solution for that but I am building a external box system which should be adaptable to the task
  12. glad that you got it working so easily! most of the motors which already have a pilot tone generator or a encoder of some kind installed are pretty easy to adapt to use your existing speed control systems. The tough part is to actually design and manufacture the speed control. You need to make custom circuit boards by yourself and so on. It becomes very tricky and time consuming very fast. So you want to get a usable square wave signal from the pilot tone generator and to have a way to use a microcontroller system like Arduino to control your brushed motor power. If it is a true generator it probably outputs some kind of sine wave. You do have a oscilloscope I assume? if not, now is the time to purchase one. Because you need to confirm what type of wave the pilot tone generator outputs and how many cycles you get from there per motor revolution. I use laser tachometer and oscilloscope to measure this data. First it is useful to run the motor normally and measure the voltage of the pilot tone generator output with a multimeter to ensure the voltage range is correct for your oscilloscope. After confirming the pulses per revolution count, the waveform and the voltage range you need to design your own preamplifier which converts the sine wave or "almost sine wave" to a square wave with proper voltage and proper duty cycle so that your sync system can use it. Ideally you would convert it to 5V peak square wave with 50% duty cycle and feed that to the microcontroller which does the speed measurement stuff. Then you do you programming magic to measure the needed info from the signal. And you will generate a correction signal which is fed to the circuit which adjusts the motor power. You can for example take the pwm correction signal you generated in the software and feed it either directly to a mosfet which controls the motor power, or if the voltage difference is too high for saturating the fet you can first preamplify the pwm signal to the same voltage level than the motor uses (for example you amplify the 5V pwm signal to 12V level and then feed that to the mosfet which actually controls motor power) . IF you need to amplify the signal first with a bipolar transistor before feeding it to the FET you need to ensure with oscilloscope that the transistor circuit does not distort the waveform too much. Typically it takes about 30min or one hour to get it working correctly if your software is already fully ready and tested with another system. Have you already made your simple brushed motor control code like I suggested earlier? the speed measuring one which is simple and fast to write?
  13. I should get a spare Konvas 1M body this month, if it works correctly it would be available as well
  14. it works this way because the too large upper loop pushes against the loop former creating a spring force which is able to move the film down during the exposure. It cannot be fully controlled how much the film actually moves unintentionally but the end result is just that weird vertical streaking if you do this long upper loop mistake with a Bolex
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