My problem is this: for some time now some prints have started to lose shape on the platter when feeding out, so by the time it gets to the last reel, they are hexagonal. Sometimes they even go triangular so by the time the platter has speeded up to pay out, momentum has shifted the film, and eventually they fall off the platter. Emergency measures cause us to tape about 8 plastic film cores round the print to help keep shape. This solves the problem short-term but is dodging the issue!

Why then? We have CFS platters. This prob only ever occurs in our No4 Proj room where there is no extraction from lamphouse and can get hot as hell. Is heat or humidity a factor? We do move the print from 4 to 2 and the prob still occurs but not as extreme. Could the film be wound too tightly on the platter on takeup?

oh wise people of film-tech enlighten me, as we now have two prints affected this way (Coyote Ugly + Unbreakable - sorry cant remember if they are UK or US prints as i am at home juxt now!)

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A free-hanging strip of film should lie nearly flat, with only a slight cupping toward the emulsion ("positive curl").

Do the hanging film "thingy" like John says. It doesn't cost you anything and it'll tell you a lot.
Cut off a piece of film from an old trailer about 1/2 a foot long. Tape it to the wall near the platter. If you look at the film at it lies against the wall, the image will be right side up and the sound track will be on the left. (This way the emulsion is away from the wall and it will curl "out" from the wall.) Just one piece of tape at the top and let the bottom hang free.

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In defense of CFS platters (since we have a LOT of them) I have only seen a CFS platter throw a print when one of the rollers between the motor and disc had come loose and cause severe vibration , causing the print to literally shake off the deck., besides that I have NEVER had a CFS platter toss a print... I have had AW3's (A platter I prefer over the CFS hands down) that would launch prints like crazy, until I timed them to the Film-tech specs and have never thrown a print since with an AW3...

It's not only the condition of the prints because of the low humidity you should worry about. I am sure that your local health and safety inspector would take a very dim view of running without extract on the lamphouse.

I agree with Dick. Even with today's "ozone free" xenon lamps, a small amount of ozone may be generated by the high voltage ignition and the ultraviolet energy. Ozone is needed in the upper atmosphere, but is NOT good to breathe. Lamps should be vented to the outside air. As noted, unvented heat from the lamp will make the projection room hot and excessively dry.

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John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com

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Thankfully, the little theater chain I am part of does not cut booth budgets. If I thought I needed booth related items and parts, they want it ordered NOW!!!

We are now in the process of installing an extraction system for the lamphouse in 4, so will see if that solves our problem.

We happen to be in a special position in that our cinema is run by pro's, not just elevated supermarket managers, so they know that when something is needed in the projection room, they give all the help they can. They know that the booth is the most important room in the place, and not the confectionary counter!