Film-Tech Forum ARCHIVE: Screen Cleaning

This is topic Screen Cleaning in forum Ground Level at Film-Tech Forum ARCHIVE.

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Posted by Russ Levinson (Member # 7185) on 07-24-2014, 03:28 PM:

Has anyone heard of or used High reach Services? They claim to clean movie screens(including silver). Prices quoted are decent and they are based out of Tampa area, but seem to have people in other states.
Anyone know this company?

Posted by Louis Bornwasser (Member # 3063) on 07-24-2014, 04:23 PM:

No, but cleaning a screen most times ruins it. More likely to just move the dirt around and it clearly removes any sheen it had when new.

Buy a new screen when it is bad. 3-5 years.

Posted by Mike Blakesley (Member # 26) on 07-24-2014, 05:24 PM:

We hired a cleaning service a couple of years ago. They were going to "deep clean" the floor, scrub the seat pans, backs and armrests, and "high dust" the auditorium. They did an OK job on the dusting and the seats (although they were sloppy on the cupholders), but the floor they just power-washed. They didn't scrub anything, so it was nothing special. You just can't replace the old stiff-brush-around-the-legs approach.

I've noticed that the sales people for those companies are always real friendly, well-spoken people, but the crew that comes to do the work may not speak English, and which makes it difficult or impossible to communicate with them. After about 3 tries to get those guys to do what their sales guy had promised they'd do, and being maybe about 75% happy with the results, and sick of them not understanding what I was saying, I just gave up, paid their stupid bill and waved goodbye.

Now we just have our concession crew come in when they want to earn some extra money and give things the deep clean. They work fast, they speak English and they do just as good a job.

Posted by Randy Stankey (Member # 64) on 07-25-2014, 05:45 PM:

You shouldn't really have to do anything more than an occasional dusting with an anti-static brush. Should you?

(Accidents or vandalism notwithstanding, of course.)

Posted by Mark Gulbrandsen (Member # 72) on 07-25-2014, 07:35 PM:

Wet cleaning any screen ruins it the first time. All one can do is vacuum off the back and dust the front once a year with a screen brush. That scam artists once made a living off unknowing theater owners always makes me giggle. Beware... Some of those scammers may still be out there! Louis is correct on screen life span.
Deep cleaning the auditorium regularly is a very good idea. Keeping the building clean will only prolong the life of everything in the auditorium including the screen.

Mark

Posted by Randy Pryde (Member # 7488) on 07-25-2014, 10:47 PM:

From the Harkness Screens website:

Care and Maintenance

The general environment where the screen is installed should be kept reasonably clean to avoid dirt and dust build-up. Screens can be periodically cleaned using a soft brush or cloth, doing this vertically with limited pressure. Screens can be cleaned using a damp cloth wetted with water and a mild detergent. Under no circumstances should screens be cleaned with abrasive materials or harsh chemicals such as acids, bleaches or solvents. Harkness Screens is not liable for damage caused to screens through the use of inappropriate cleaning methods or chemicals.

From Severtson:

Cleaning Instructions for Optically¬Coated Materials (Includes Stellar White, High Contrast Grey, Grey Vision, and SēVision 3D GX)

1 Brush screen surface softly and lightly with a clean, dry micro¬fiber cloth to remove any loose dirt or dust. Do not use sharp instruments.
2 For tougher spots, attempt to remove using a non¬moisturizing/non¬oily detergent (diluted to 20% strength), water, and a cellulose sponge. Blot lightly with cellulose sponge, working from the bottom of the screen and moving up in sections. Use clear water in the same method to rinse any solution off and blot with a clean damp sponge to remove excess water. Cleaning should be done in the shade (not in direct sunlight).
3 Never attempt to use solvents, commercial cleaners, chemicals or any abrasive type cleanser on the screen.
4 Spot cleaning areas of the screen is not recommended. Doing so may can lower image quality or give uneven projection. If the screen has dirt and dust on it, wash the entire screen as described in 2, and dry with a large damp cellulose sponge or chamois, softly applied, to prevent water spotting or streaking.
5 Keep your screen clean and avoid getting any foreign materials on it. Cleaning or removing scratches, paint, ink, nicotine stains, etc., may prove difficult if not impossible.

Posted by Steve Matz (Member # 1890) on 07-26-2014, 01:35 AM:

Here is a U-TUBE Instructional Video on Cleaning a Matte Screen!

https://www.youtube.com/watch?v=EghQaD5hGns

Posted by Mark Gulbrandsen (Member # 72) on 07-26-2014, 11:29 AM:

The video should really be called. "How To Leave Uneven Vertical Streaks On Your Vinyl Screen"

Posted by Frank Angel (Member # 248) on 07-26-2014, 02:02 PM:

quote: Mark Gulbrandsen
Wet cleaning any screen ruins it the first time. All one can do is vacuum off the back and dust the front once a year with a screen brush. That scam artists once made a living off unknowing theater owners always makes me giggle

Giggle all you want, Mark, but experience has taught me that you are wrong about this.

We had a fellow out of Texas I believe clean our screen. He had a system using a dual T device that had one cross bar with the cleaning solution and the second dry cloth which would catch are remove the dirty water right after it was applied. The top cross bar (which was about two yards wide) was wrapped with very soft flannel over sponges. The lower bar was flannel over cotton. He had about ten of theses that he could attach to a pole and he would do this process of cleaning/wiping across the surface. It was a very slow and laborious process across 50ft, but I can tell you, it worked and with no damage whatsoever to the screen. Ours was a "pearleascent" medium gain screen without perfs. White light projected on it after the cleaning showed NO streaks whatsoever, something which he guaranteed before hand.

We have always had a no-smoking policy so smoke contaminated air was never an issue and I am sure that is why our screen lasted for so long - about 15 year before it showed it's age. The cleaning gave it another 3 years before we replaced it. Also, I think the fact that it is non-perf makes a big difference in how dirty a screen gets. Unless you can get a zero air pressure against the screen, dirty air flow thru the perfs will catch a lot more dust and contaminants than a non-perf screen.

Years ago a screen installer handed me what he called a reference swatch of the screen he was installing. He said to keep it in a sealed, air-tight container. Any time you need to know how dirty the screen has gotten or how much the material has yellowed, just get out that reference swatch and hold it up to the screen. Light meters can tell you if the screen has lost reflectivity, but not if it has yellowed. The reference swatch shows you immediately what the condition is of an aging screen.

Posted by Steve Matz (Member # 1890) on 07-26-2014, 04:30 PM:

I'm glad I found this Video because when it was over there was another Video on cleaning the Color Wheel and Prism Lenses on my 3 yr old 73" Mitsibishi. I have never had to do anything to it but replace one Projection Lamp.The color has always looked good but I decided to follow the whole video and tear the Unit down anyway. I couldn't believe how much Haze was on the color wheel and 3 other lenses in the unit. After I did what was in the video including adding two 1.5k resistors across the Chips that control the cooling fan speed; I couldn't believe how much brighter the picture was and how much richer the colors look.

I suggest if you have a DLP TV to find a video up on U-tube and follow step by step of what to do and correct on your model TV. If I hadn't come across the Video for cleaning the Movie Screen I probably would have been satisfied with the Picture I was watching before the Fix. My TV Picture actually looks better than I can remember when it was new; also by doing that revision where I sped up the cooling fans,I probably have added more longevity to my Lamp... LUCKY ME [thumbsup]

Posted by Marcel Birgelen (Member # 6801) on 08-06-2014, 02:02 PM:

I always clean my screen Chuck Norris style, with a 20,000 PSI pressure washer and a few roundhouse kicks to get the kinks out.

While I do believe that you can, theoretically, wash a normal white vinyl screen if you're super careful, I highly doubt you can do this with a silver screen, without doing irreparable harm. Maybe the damage isn't visible to the naked eye, but will visibly harm the polarization during 3D presentations, causing an increase in ghosting artifacts.

quote: Frank Angel
Also, I think the fact that it is non-perf makes a big difference in how dirty a screen gets. Unless you can get a zero air pressure against the screen, dirty air flow thru the perfs will catch a lot more dust and contaminants than a non-perf screen.

A perforated screen will also dramatically increase the surface dust and dirt can attach itself too.

Posted by Mike Blakesley (Member # 26) on 08-06-2014, 03:44 PM:

John Eickhof gave me this procedure for screen cleaning:

1. Dust both sides of the screen with screen brush
2. Make a very weak solution of dish soap in water (just a little soap, not very much)
3. Soak a bath towel in the solution, wring it out slightly so it's not dripping, wrap it around the screen brush and then wipe the screen top to bottom (re-soak the towel after every stroke or two)
4. Do the same process again with the towels wrung out as much as possible
5. Finally dry the screen with dry towels using the same strokes.

I only used this procedure once when we were trying to "recover" from a customer flinging a large wad of gum onto the screen. The gum pulled off the matte coating, leaving a very obvious bright spot when a picture was projected;, so we wound up replacing the screen anyway. But the cleaning didn't do any harm to the rest of the screen, as far as I could tell.