Film-Tech Forum ARCHIVE: Question about film cleaning

This is topic Question about film cleaning in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Joe Beres (Member # 678) on 10-10-2001, 01:02 PM:

If these questions have been covered before, please let me know, but I don't remember them being asked in the past.

I run a University screening room that runs films for the film department as well as a weekend film series. We have a pair of Ballantyne Pro 35 projectors, and we run only 2000' reels. We rarely run a film more than once a semester, but I would really like to have some sort of cleaning system in place, especially for the prints that are in our collections here. Here are my questions:

In this sort of set-up, how can a system like the Kelmar/Film-Tech be mounted to a projector? We don't currently have penthouse readers, but that is in the works for the future.

Is there a way to use a cleaning system with a rewind set-up? We have two reel to reel rewinders right now, a Goldberg Model B and an older copycat of the Goldberg. Would we need a different kind of rewind system?

Any advice along these lines would be appreciated. Thanks.

Posted by John Pytlak (Member # 331) on 10-10-2001, 01:57 PM:

Whether you use a Kelmar or Christie web cleaner dampened with FilmGuard, or a Particle Transfer Roller (PTR) film cleaner, you should clean the film while it is moving no faster than the normal projection speed of 90 feet per minute. IMHO, in your 2000-foot changeover situation, it is best to mount the cleaners on the projectors, and clean the print while it is being projected. But you can also use either type of cleaner "off line" in a rewind situation IF you don't wind the film too fast. I suspect your Goldberg winders are much too fast.

Some guidelines for film cleaning are on the Kodak website:
http://www.kodak.com/country/US/en/motion/support/technical/hand2.shtml#cleaning

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Research Labs, Building 69, Room 7525A
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Jeff Taylor (Member # 443) on 10-10-2001, 02:36 PM:

At the risk of getting whooped on by Brad, John, and the guys let me first say that I agree with John's earlier post. I also feel, however, that any cleaning is better than none and that you can do a respectable job, albeit with lots of labor, with only rewinds, cleaning chemicals, and a soft pad such as a Webril Wipe. For very occasional showings such as your situation a Kelmar cleaner and Film Guard may not show its optimal performance as it was designed for repeat application in a platter/cinema situation. On the other hand, Film Guard does perform magnificiently with the hand wipe application mentioned above WHEN USED VERY SPARINGLY. The dirt you pull off the film will shock you and it will eliminate base scratches on projection. If you do use a typical volatile cleaner, just be careful to let it dry fully before storing the film. Before switching to Film Guard I used to apply it with one winding, and then immediately rewind through a nearly dry cloth to make sure there was no spotting. Correct and perfect, perhaps not, but it has worked for me for more years than I care to mention and I've never damaged a print.

Posted by John Pytlak (Member # 331) on 10-10-2001, 02:44 PM:

Jeff said: "I also feel, however, that any cleaning is better than none and that you can do a respectable job, albeit with lots of labor, with only rewinds, cleaning chemicals, and a soft pad such as a Webril Wipe."

Your "traditional" method of film cleaning works well, and is described in the link I gave:

"Cloth/Solvent Sandwich

Thoroughly moisten (but not dripping wet) a pad of deep pile, lint free plush with an approved film cleaner and fold it around the film. Draw the film through the sandwich of cloth at a speed that is slow enough to allow the cleaner to evaporate before the film reaches the take up reel.

Winding up wet film causes spots and blotches. If ceiling space permits, you might consider installing an idler roller above the cleaning station to provide a longer film path from the cleaning cloth to the take up reel, thus enabling the winding speed to be increased. As the cloth begins to dry, or when a complete layer of cleaning solution can no longer be seen on the film surface as it emerges from the folded pad, stop, refold the cloth to provide a clean surface to the film, add more cleaner, and resume winding.

Be sure to wear plastic or rubber gloves to protect hands against the solvent's ability to draw the natural oil from the skin."

As you note, be sure not to apply too much film cleaner, such that the print has "oil mottle" or gets too slippery.

Posted by Brad Miller (Member # 2) on 10-10-2001, 03:14 PM:

Just in case anyone mis-understands John's explanation of hand cleaning on the bench, those instructions are referring to trichlourethane-type of cleaners (Renovex, First Run, RTI, etc) and not FilmGuard. There is no need to wait for the solvent to "evaporate" when cleaning with FG, because that's the idea.

I do firmly agree, ANY kind of film cleaning is better than nothing.

Posted by Joe Beres (Member # 678) on 10-10-2001, 03:19 PM:

Thanks for the advice, fellas. I've used the sandwich method before, but I'm usually too busy to take the time to give the print the proper "hand" cleaning, but it is good to know that FilmGuard can be used for the task. Is FilmGuard good for my situation? Our prints would receive a treatment whenever run, but that would be only 1-4 times per year at best. Are there any archival problems with FilmGuard? It doesn't seem like their would be, but that would be an issue with our collections here.