Thanks for sharing. I was a projectionist at a local theater in my 20s, and I have very fond memories of working with the older machines. There was something so satisfying working them on Summer nights in the booth alone.
The move to digital projectors everywhere was very shortly after I left.
Always cool to see people help keep the medium alive.
Be careful about using AOI cpu coolers for other purposes. They are enclosed units subject to evaporation and air infiltration. Fluid levels will drop over time and refilling is difficult. Also, be wary of orientation. You want to make sure that the inevitable bubbles are not repeatedly drawn into the pump. So you want to position the radiator with the in/our ports lower, giving a low-turbulence chamber towards the top of the radiator for bubbles to accumulate.
Opinions differ, but 800+watts through a 2-fan radiator, in an already hot environment, is likely not enough. If this was an 800-watt CPU I would be going with either some wickedly powerful fans or 2x as much radiator.
One thing seems odd: it takes an 800W LED to double the light output of a 250W halogen bulb. Normally LED is far more efficient than halogen so I wonder why the opposite is true for this project.
Interesting that the film material had better color retention than the old projectors. I never thought about it before and assumed that the washed out colors of old 16mm projections came from bad recordings.
Super awesome project. As an embedded engineer who grew up in the arthouse/program cinemas of Berlin, I wish I had heard about this two years ago. Would have loved to help out.
Neat stuff! I have a ton of 8mm and some 16mm film to archive, perhaps this is a good first step towards an open-source film scanner.
Question: the blogpost mentions archivists needing 16mm projectors. Now I assume they would use these projectors to archive 16mm film but how / why?
Why not scan film in instead of.. projecting it on a wall and filming that to archive?
At least thats what I’m extracting from the blog with my fair but limited knowledge, if someone could enlighten me it’d be greatly appreciated!
Curious: Why do they need to support all those different frame rates?
Former 35mm projectionist here (see https://news.ycombinator.com/item?id=35887809). I also worked with 16mm projectors and cameras as a student.
It's cool to see that people are still interested in this media, and trying to fix a number of problems. There are a couple things about this proposal that are admirable, such as switching to dimmable LEDs and open-source/3D printable parts.
I also liked the bit about not trying to reinvent the wheel ("We believe that especially the central mechanical elements of the old projectors – claw mechanism, shutter wheel and film transport - are in most cases so well engineered that a new development here would be a waste of time and energy.") But what follows is an extensive list of new specs that would make the project vastly more complex.
16mm/35mm is already fading, with a finite population of prints that dwindles every year as film deteriorates or reels are lost/destroyed. Some of the technical features ("Manual vario-speed from < 1 to 30 FPS") are a niche within a niche. Really, how many artists or experimental studios are there who want to play back a 16mm print at .75 FPS? Who would watch them?
This project would be far more realistic if such features were scaled back and the focus was on getting a bare-bones, open source projector that works with 16mm optical film (the majority of existing stock) as well as some of the low-hanging fruit on the list. I think is doable. Low cost, simple plastic film projectors were once a thing with another type of film (Super 8, see https://en.wikipedia.org/wiki/Super_8_film)
If hard stuff is added to the list, at least focus on practicality for a wider range of people, such as a tool to safely evaluate print quality before playback at normal speeds or some sort of print cleaning mechanism for reels that have been sitting in someone's basement for 30 years.