But, all is not lost. I found out the major cause of this bubble. It was caused by the platter being too close to the projector. If the lamp is out of focus or the if the dichloric filters are shot, the heat from the lamp collected on the film will not dissipate fast enough before it starts winding on the platter.

Result?

Tension building up in the convolutions. The problem was corrected by moving the platter at least 10 feet away from the projector. Other factors come to play, such as relative humidity, ambient temperature, etc. but did not seem to be the major cause.

I fought that problem for several weeks before I made my little discovery.

The pic I put up is of a print that was atually roped. The hump is from the dents in the film pushing the layers apart. You'll also see the convolutions "weaving" up and down as it winds up on the platter. That's from the film trying to settle as it winds up.

I'm not proud to say that I'm getting good at diagnosing this problem. People will call me up and say, "The film is all staticy and I don't know why." Almost every time I go there I find the print spiked. This is why I took that picture. All I have to do is e-mail it to them and ask, "Is it like this?"

There's a rumor going around the circuit that Bounce will help. If all else fails, I have a box of it in the cabinet, but logically, it shouldn't work because its normally activated in a very hot dryer, not in room temperature.

One of our engeneers, who used to work at a very big lab, has experimented with all sorts of static solving problems. He suggests running the film upside down back to the platter and then back upright the next show; wiping static guard on the edges just like you say to use FilmGuard. Also, vacuming the booth at the end of the night and then pumping massive amounts of static guard (FilmGuard?) into the carpet to sit overnight. Restricted traffic then lessens the static.

Marbles are good too. Not always effective, but sometimes. Just roll a couple steel marbles on the platter and they should break apart any film that clings and gets to them.

Are platter systems grounded? Seems to me attaching a metal thing from the platter to the ground wall outlet should conduct static off the film.

As for thrown prints, I always hear to use suction cups, or suction cups with tape, and lots of them. Christie makes a hocky puck looking suction pad that when cleaned regularly, wont slide and definitely wont allow a print to throw. I use them on all my platters and havent thrown nuthin.

Two easy steps:
#1 Fix your equipment (meaning time the platters properly) so that they do not have the tendency to sling prints.

#2 Run media pads soaked in FilmGuard *or* wipe the edges of the print with FilmGuard. The FilmGuard kills the static. There's nothing left of it!

Maybe it's just too simple. Still, I have yet to have a brainwrap or a print toss in this manner. What's next? Some new way to use egg yolks to stop static?

Some of us have engeneering bosses who do not understand how to use filmguard and thus get mixed results in testing it and it doesn't get rolled out. Skeptical tech's further this stalled situation. In the mean while, I'm getting my filmguard from a friend and experimenting with other methods.

Misaligned (too-tight) pad rollers also cause this problem.

As for the theatres that aren't using Film-Guard and still launching prints you should seriously look into the Film-Tech method of timing AW3s, it works fantastic! Some minor tweeking is sometimes required but once dialed-in the platters perform flawlessly. In rare instances the platters may oscillate on taking up but Bevan at Christie says that is caused by a failing photocell or LED.

As for real static: GET FILM GUARD! NOW! the cost of FG is miniscule compared to the amounts of tickets refunded and damaged print costs from wrapped or thrown prints!!!! Don't experiment with snake-oil methods like Cling Free Sheets or Bounce... The only other approved method would be a humidifier in the booth (NOT-I repeat N O T) a 'vaporizer' or a device that actually emits a visible mist! Those will damage film, electronics, and metal items in a hurry!! A 'swamp cooler' is the ideal way to get more humidity into a booth, but they can be somewhat expensive. Smaller humidifiers are available but make sure that they are true evaporative units and not ones that emit a mist.

Hope this helps!

Aaron

Neither did platter timing, guide roller alignment and wear verification, or uneven film tracking through the guidance kits, sprocket changes (in case one was straining sprocket perfs), or re-establishing the crown of the platter because the spacers fell out over the years. Re-focusing the bulb helped, but did not cure it. My filters are probably shot. I even went so far as to check the exhaust blower to make sure I had enough draw. Relative humidity and ambient temperature did not seem to be a major factor in this booth.

But moving the platter further away from the projector CURED the Monkey Hump.

Film-Guard is very good and will stop lots of problems, it will kill static. But it is not a cure-all.

As Brad suggested, a little preventative maintenance on the equipment will go a long way.

And, if they jerk hard enough and the crown shims are missing from the CFS platters, it could very well toss your print.

At our theatre, one of the projectionists came up with a great idea for completely eliminating film breaks due to static. We found out that the bubble in the film moves around the brain on the platter and always tries to jump one roller in the brain. (We use the strong platters) I've seen it so many times.

Our solution is simply this...

The theatre across the street (owned by the same company) recently closed down. It had a 70mm with 3 or 4 70mm brains. We took all of the outside protective rollers off of it, and went around to our 32 brains, and replaced that one roller that the film ALWAYS jumps with one twice as tall.

I remember the night we installed them... in the credits of "Coyote Ugly" I watched the film start to loop around, the next layer pushed it up, and it couldn't make it over. It was incredible.

Since we installed the system about a year ago, we have not had a SINGLE film break due to static. If anyone is interested, I will take a picture and post it.

Looking at the Christie brains, I don't know if it will work, but I know it will on Strong.

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