On Wed, Aug 26, 2015 at 03:06:33PM +0100, Malcolm Smith wrote: > Matthew Hunt wrote: > > > My understanding was that commercial film recorders didn't work by > > projecting an image and photographing it, but rather by directly > > exposing dots onto the film using tiny sources of light. Think of how > > an inkjet printer head sprays tiny dots of ink, then imagine it > > spraying drops of light instead. > > > > But I never looked into the technology very much; I could be mistaken, > > or multiple techniques might be used. > > George Sinos wrote: > > > Matthew is correct. They called them "flim recorders." The film was > > exposed by colored lasers. Cost a lot and finicky to setup. All the > > disadvantages of film with even more inconvenience and expense. We used > > them at work before digital projectors became ubiquitous. > > > > I am curious why you may want to do this. Digital projectors are in the > > $300 range and are much better than slide projectors ever were. > > Considering the cost of film and processing, a projector would quickly > > pay for itself. > > Thanks. > > I assumed the more sophisticated (and more expensive) companies used a more > professional method. I know little about film recorders and I'm sure what > little I heard was connected to Polaroid film, but I've never had to find > out detail about them. I've seen such a range of prices and I'm sure that > one at the very lowest price range implied copying by the methods I want to > try.
While later film recorders may well have used lasers, that's not how the original models worked. Back in the 1980s I had access to a film recorder where I worked (Apollo); we used it to make slides for images that we were submitting to SIGGRAPH. Inside was a small monochrome high-resolution CRT, and a rotating filter wheel. Each of the three colours would be exposed in turn (the camera shutter would be open for the whole time). We had multiple interchangeable "backs" for the unit; one with a modified 35mm SLR camera, two Polaroid backs (one 4x5, one 8x10), and even an Oxberry animation camera (basically a 35mm movie camera). The Polaroid backs were single-frame only, but the SLR had a motor drive, so you could expose an entire roll of film sequentially. The movie camera, of course, also had motorized film advance. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
