Film Path (w/out gate)
There are a ton of variations on how many rollers, roller placement, use of PTR (particle transfer rollers), pinch rollers, sprocket rollers, etc. This section is intended to focus on how to achieve a good balance between cost and maintaining proper tension.
Here are some screenshots of how other systems are laid out:
The common factors seem to be:
- drag on the feed reel
- tension throughout the system
- no-slip in film advancement mechanisms
- touch the film as little as possible, except when using PTRs.
A note on PTRs - these are generally sticky rollers and can be used to advance the film reliably, as seen in the Kinetta. It’s a clever way to advance the film without pinch rollers or sprockets. The only drawback is they’re hard to source. The only ones I’ve been able to reliably source are from Kodak. They’re expensive and I’m not sure if they’ll be around much longer. There are others that exist, especially in the paper printing industry, but I’m not sure where to start. I’d love to know where they sourced the yellow PTR rollers in the Cintel scanner. Any guesses on where to look for these types of rollers?