Where I come from, clean, white cloth baby diapers are the traditional thing to use.Be careful and "blot" as much of the stuff away as you can, instead of wiping. You don't want to spread the mess.
Have a professional do it. You could do it yourself but it's a PITA and if you mess up it'll look worse. It's well worth the money.
Cleaning a small area?
Splotches made from soda "spills" (and similar stuff) can usually be wiped off if you get them when they are fresh. Use a clean, WHITE cloth. Do NOT use anything that's colored, lest the color in the cloth come off on the screen! Where I come from, clean, white cloth baby diapers are the traditional thing to use.
Be careful and "blot" as much of the stuff away as you can, instead of wiping. You don't want to spread the mess.
If it's had a chance to dry or if it doesn't want to come clean that way, you can use clear water IF YOU ARE CAREFUL! The problem you will run into is that you might make a clean spot. It will stick out like a sore thumb when you show the movie.
Don't soak the screen. Just dampen the cloth and wipe gently. Once you have it cleaned let it dry and step back to look at it. You might want to show a picture or just some light on the screen. If you see a clean spot, you can carefully "feather" the edge of the spot. That means you go around the edges of the spot and gently blend the clean part into the dirty part. If there's a gradual transition it'll be harder to spot.
If the screen has any texture to it or if you can tell that there is a "coating" on it you probably should NOT use water on the screen. You could permanently stain/damage the surface. If you can't get it clean yourself, using just a cloth you should call in a pro.
If you have cleaned the screen more than one or twice, or if there is crud over a substantial portion of the screen you should call in the pros.
Other than that, the most you should do to clean you screen is brush it with a screen brush every week or so. (Or whatever schedule your company recommends) If you keep the spitballs, gum wads and Gummi Bears off the screen you should really never have to do much to clean it, except for every once in a while when you have the pros come in.
With matte screens, clean any spots quickly, before the stain "soaks into" the PVC and sets.
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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
There was another fellow who did a lot of the work for Al (Broken Hand?) who might have started his own company.