How programmable are 35mm projectors?

[Marin Zorica]

Back to basic thing, i did something similar recently, only we did not use slide projector, but profile projector with some gobos. Than i just added simple automation with mocrocontroller and programmed steps as wanted by user. Same think you could acomplish by using slide projector which have automated exchance of slides. There should be somebody with some electronic knowledge to interface some kind of automation (arduino, raspbery pi, even some cheap plc...) to projector for triggering slides.

[Randy Stankey]

I don't see any reason why an Arduino or a Raspberry Pi couldn't do the job. As I remember, the remotes on most slide projectors work on simple contact closure. An Arduino/Pi could easily do that.

I have messed around with microcontrollers like that but haven't gotten into a lot of detail. For somebody who has experience with them, making a remote system for a slide projector would probably be a nice weekend project.

[Martin Brooks]

As others have stated, programming multiple 35mm projectors was a big thing before computer graphics and quality video projectors. There were a number of companies who made programming devices and dissolvers, but AFAIK, they're all gone. One of the leading companies in that market was AVL (Audio-Visual Laboratories). They started out with programming devices that used punched paper tape, moved on to electronic pulses that were recorded on tape along with a soundtrack and eventually developed computer-based programming with time code. IIRC, one of their devices was called The Eagle. There were a number of journals that covered the field and even some trade shows.
Usually, you stacked the projectors three at a time. There were shows with as many as 30 projectors, but. most of the ones I worked on were either three projectors or nine projectors.
Here's one of their programming systems, but there was also a separate box that was the dissolver that you connected to each stack of three projectors.

I don't know how it could be done today.

[Sean McKinnon]

Mark,

Did you ever get to work with an EC/ECII or E series from Kinoton?

[Mark Gulbrandsen]

Sundance had or may still have a Kinoton Electronic. I ran it a couple times but it had image bounce problems with the old prints they wanted to run. I declined operating it again after that. I do know that Larry came out and upgraded it, and then it ran fine. But that was my only experience with them. I had a PK-60D in my home screening room that was awesome. A collector friend near Salt Lake City has it today and also loves it. The post houses in Chicago that I serviced still had Magna Tech's. But only one of those was electronic. I ended up with Chicago Editel's FR-35B, and it was awesome. Had optical registration via sensors looking at the perfs that corrected the stepper position ever so slightly. The earlier FR-35A is an awful machine. Astro film lab in Chicago had one.