Film-Tech Forum ARCHIVE: Film Gaurd Scratched a print?

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Posted by Micheal Turlock (Member # 1892) on 09-25-2003, 06:55 PM:

It's happened to me twice now, I have been running Film Gaurd on the first showing of a new movie and on the second show we notice light base side scratches. The first time it happened it was so bad it looked as if the actors were marionettes dancing on screen!

My Managers' best guess is that the sound drum has an excess of Film Gaurd on it and small dirt particles may have scratched it there.

Has this even happened to anyone before? Do you think the sound drum is where it may have been scratched?

I am running off of a Strong Platter system and into Century Projector.

Posted by Adam Martin (Member # 641) on 09-25-2003, 07:22 PM:

What film cleaner are you running on and what brand of media are you using?

Posted by Aaron Sisemore (Member # 145) on 09-25-2003, 07:22 PM:

Unless you are contaminating the media with an abrasive of some kind or running used dry media, you should be getting scratches of any kind from a film cleaner.

The problem lies somewhere else in your film path, as you say it has only happened twice (assuming twice in a good number of screenings).

If you are seeing any slippage in a Century sound drum, it is likely to be either too little tension, failing sound drum shaft bearings, or a combination of the two. Seeing you are reporting that its not happening every time, I am leaning toward a threading error of some kind.

-Aaron

Posted by Sam Hunter (Member # 1119) on 09-25-2003, 08:19 PM:

How can a liquid scratch anything?
Your pads must have something abrasive in them somewhere, or somebody dropped a taco in the bottle while you weren't looking.

Posted by Brad Miller (Member # 2) on 09-25-2003, 08:48 PM:

FilmGuard cannot scratch a print. That simply is impossible. The scratch has to be coming from either excessive tension on the cleaner (not possible with a Strong platter), bad media (doubtful), bad bearings in your sound drum that is causing it to freeze up, a defective cleaning machine, or an operator misthread.

Can you spin the sounddrum by hand with minimal effort? When you let go, does it continue to spin on it's own for awhile?

What kind of media are you using?

Strong platters do not have a keeper roller on every roller in the takeup chain. Many times I have walked into a theater running and the film on the takeup path was dragging over a roller's shaft instead of being ON the roller.

Are you SURE that the media advanced during the show? Far too often people blame bad media or something else on a scratch, when it is the person who loaded the film cleaner in the first place who did not tighten down the thumbscrews, or properly secure the head of the media to the takeup shaft, or the cleaner is missing (or cannot grab) the takeup cores. Heck, for that matter if your cleaner has ever been dropped and the main flywheel is tight in the least bit, Strong platters do not have enough backtension to force them to spin. The result is the media does not advance and you scratch the print.

There are a lot of possibilities here. Give us all the info you can...especially a detailed description of the scratch location, if they move around or jiggle, vertical/horizontal/diagonal, etc.

Posted by John Pytlak (Member # 331) on 09-25-2003, 08:57 PM:

I agree. Check your film path for abrasive components that may be scratching the film in the image area. In most cases, it would be something that contacts the full width of the film, like the sound drum or cleaning media laden with abrasive dirt. Are you reusing the media many times, or trying to clean a print that has so much abrasive dirt (construction debris?) that it quickly overloads the cleaning media? Do you have the film "pulling in" to the center of an undercut roller because of excess tension?

Posted by Paul G. Thompson (Member # 655) on 09-25-2003, 09:37 PM:

I have a tendency to agree with John. Sounds like a media pad had something abrasive on it....

Make sure the scanner drum turns freely without any binding.

Posted by Micheal Turlock (Member # 1892) on 09-25-2003, 09:59 PM:

It was a new pad on a Kelmar Cleaner. I think that it is just the Generic Media (white media on a cardboard tube). I don't think it was the media (the image looked perfect on the first run), it was on the second run that we noticed it. That is why we think it may be abrasives on the sound drum that may have caused it. There are a lot of vertical scratches all across the screen, that stay very steady in the same place throughout the show.

In the forums that people were cleaning films by hand during the make up. How do you do that? what kind of cloth would you use?

Posted by Paul G. Thompson (Member # 655) on 09-25-2003, 10:13 PM:

Make sure your cue detector is threaded properly. Also check your return path to the platter. There may be a jammed roller. I don't know of anything in the Century that will cause a baseline scratch as you described. The only way the sound drum will scratch a film is if it is not rotating or dragging.

Give the sound drum a spin....it should take a good while for it to slow down and stop. Compare that test with another machine.

Posted by Joe Redifer (Member # 3) on 09-25-2003, 10:44 PM:

I don't think the actual cleaning has anything to do with it if you didn't notice it on the first run. It's scratching AFTER the gate.

Posted by Brad Miller (Member # 2) on 09-25-2003, 11:56 PM:

quote:
In the forums that people were cleaning films by hand during the make up. How do you do that? what kind of cloth would you use?

No, no, no, no, no, no, no. Bad idea. Cleaning by hand vs using the Kelmar media cleaner is a no brainer. The media cleaner will ALWAYS do a far superior job. Don't even consider this since you have a cleaning machine at your disposal.

Posted by Darryl Spicer (Member # 711) on 09-26-2003, 02:06 AM:

sounds to me like it could be the sound drum not turning freely as stated in above posts. CHeck the drum for free turn as mentioned above.

Posted by Micheal Turlock (Member # 1892) on 09-26-2003, 03:44 AM:

I checked the sound drums on the two projectors that have had these scratches and the both spin freely for nearly a minute.

We did notice that there was lot of Film Gaurd on the sound drum after the show (we were expexting as it says in the instructions) but do you think that dirt and dust may have collected on the film gaurd and as it passes through the sound drum it got scratched? - That was my managers best guess as to what happened, I just wanted to see if anyone else would have a better guess.

-Thanks for all the help!

Posted by Stephen Furley (Member # 1277) on 09-26-2003, 04:14 AM:

Joe wrote:

quote:

I don't think the actual cleaning has anything to do with it if you didn't notice it on the first run. It's scratching AFTER the gate.

Not necessarily, it could be happening above the gate, but just didn't happen on the first run. The entire film path needs to be inspected to find the cause.

Even if the cleaning media were contaminated by abrasive dust they would be less likely to scratch the film if used with Film-Guard than if used dry.

Contamination of the Film-Guard with abrasive material is possible, but unlikely, unless removed from its original bottle, and stored in an open container, I can't see why anyone would do this.

About the only thing which couldn't possibly cause this is the Film-Guard itself.

Posted by Brad Miller (Member # 2) on 09-26-2003, 04:17 AM:

What print was this? The sound drum residue problem is a thing of the past. It doesn't affect current release prints, but was noted in the instructions for completeness. Besides, even if you had a huge amount of whatever on your sound drum, so long as the drum is spinning freely it could not have caused your scratches.

Find someone at your theater who has a digital camera and get them to take a few screen grabs of the film scratches during a scene where the actors are not moving around much and the scene is brightly lit so we can see what kind of marks you are getting. Just being able to see the marks will help us rule out a majority of possibilities. If your "green bands" on your trailers have the scratches, that is perfect to take a picture of, as the green shows scratches very well.

Be sure to include a shot of your used media pads after one of your "scratched" screenings as well. I can identify a lot of things just from seeing the media roll.

Just out of curiosity, you do have actual FilmGuard and not the fake CPI product, right?

Posted by Mark J. Marshall (Member # 1409) on 09-26-2003, 08:28 AM:

It's not the Film Guard, I think we all agree on that. But I've seen projectors with rollers not spaced far enough apart to allow for the addition of the cleaner which resulted in the print getting stressed or twisted in a wierd way when the film cleaner is added. In fact, sometimes the film would eventually come off a roller when the cleaner was added.

When I asked the projectionists there how often they clean their prints, they said they don't because it scratches the film. [Roll Eyes]

Post some pics of your projector setup too. Specifically the film path around the cleaner.

Mark

Posted by Edward Jurich (Member # 1787) on 09-27-2003, 09:18 AM:

I had a scratching problem that finally turned out to be that when the failsafe roller was installed at the takeup, it was mounted "out of line" with the take up roller in the projector. As a result, the film would at times jump out of the roller groove and put a scratch on the one side. After a few runs, the film would have several scratches. Since I realigned the failsafe with some washers, there have been no more scratches.
Someone mentioned cleaning film by hand. I've cleaned daters by hand with film cleaner. They are short enough to allow rolling them back and forth to get the excess cleaner off.

Posted by Ken Lackner (Member # 1002) on 09-27-2003, 10:49 AM:

quote:
What print was this? The sound drum residue problem is a thing of the past. It doesn't affect current release prints, but was noted in the instructions for completeness.

Why is this a thing of the past? How far in the past?

Posted by Mike Blakesley (Member # 26) on 09-27-2003, 12:14 PM:

I've been using FG for over a year and have not noticed any sound drum residue.

Posted by Paul G. Thompson (Member # 655) on 09-27-2003, 12:34 PM:

Mark, those individuals that won't make the film path should take a good look at what they are doing. I have seen some weird paths also....and and most of those can be corrected without spending anything more than what it costs to buy a cup of coffee.

One way out is to mount the film cleaner on the platter mast if there is insufficient room between the top of the projector and the ceiling. If the bracket that comes with the film cleaner is used and there is sufficient room for the the guidance hardware between the top of that thing and the ceiling, I don't think there is any excuse for having a weird film path that would facilitate the film derailing a roller.

Posted by Randy Stankey (Member # 64) on 09-27-2003, 01:09 PM:

So, scratching doesn't occur when the cleaner is not being used, no? Same projector, same film, same everything else but the film cleaner?

If so the answer seems clear that one of two things is the problem. First, the tension on the film may be too tight, causing excess friction and scratching the film. Second, mounting the film cleaner may alter the film path, causing it to rub somewhere it's not supposed to.

If you're using Strong platters, I think the film tension theory is eliminated unless you're seriously misthreading it. If that's true then you'd be seeing scratching all the time, thus this whole issue would become moot.

Now, it is quite easy to have a clear film path in "normal" conditions and a "bad" film path when the cleaner is added.

Where in the system is your cleaner located? Platter? Projector-mounted? Let's assume projector mount, for the sake of discussion. (Same principles apply for platters. Just transfer the ideas.)

Thread up some old film without the cleaner. You don't have to run the machine. Just a hunk of an old trailer will do. Follow the film as it comes off the upper roller above the projector and turns downward, into the machine. Notice that it makes a "compound bend". Not only does it make a 90º turn, going from horizontal to vertical but it makes another 90º turn as it "barrell rolls" going into the projector. This makes the alignment of that upper roller pretty tricky to get right. The position of this roller is KEY to having a clear film path. Fidget that roller around until the film goes perfectly flat over the center of the roller and doesn't hit against the keeper(s) or the flanges. You're likely to find that the roller will have to be bent into a very odd looking position... kind of pointing sideways and down a bit.

Once you have the path clear for NO cleaner, install the cleaner and repeat the process. You're likely to find that the position of the roller(s) will change slightly. This is where the fun begins. The film path for ONE situation may not be suitable for the other. You're going to have to fiddle around until you get a postion that satisfies both. It's just one of those things you're going to have to fool around with until it's right. A lot of people aren't willing to spend the time or effort to do this seemingly simple task but I would say that it's the source of a majority of scratched prints.

When you have your problem solved, tell your manager that FilmGuard is the thing that's going to save his ass! One of the properties of F.G. is that it hides scratches. If the scratching isn't so severe that the emulsion is disturbed you're likely to find that a good, healthy application of F.G. will make most, if not all, of those scratches disappear!

Solve your problem with the scratches, load up some F.G. on the cleaner and run it exclusively on the damaged print during every showing for a couple-three days. Follow all other directions exactly. You will find that the more runs of the F.G. cleaner you put on the film, the better it will be. Geez, if you can run it on that one film for a whole week, all's the better!

The only thing I would do differently than the instructions would be to make sure that the pads of the cleaner are good and wet with F.G. After about a 1/2 week, check them and wet them again if they need it. In my opinion, this is the one and only case where extra FilmGuard is a good thing. Just be sure you don't put so much on there that the film won't run correctly through the projector. (You'll get jitters.) That's why I said to wait before resoaking.

Do that and, if the scratches aren't so bad that F.G. can't fix them, show the film to your manager again. I guarantee (s)he'll be whistling a different tune! [Smile]

Posted by Brad Miller (Member # 2) on 09-27-2003, 02:24 PM:

Ken, mid 90's era.

Posted by Micheal Turlock (Member # 1892) on 09-27-2003, 03:24 PM:

Thanks for all the help!

Randy - your post will help a lot. The Cleaner is mounted on the projector so it all makes sence. I'll look over those things when I get in.

The two prints it happned to were "Pirates of the Caribbean" and "The Order" they have since left the theater so I can't show you what the scratches looked like.

I will try to get my hands on a Digital Camera so I can show you pictures of my film path.

Posted by Gordon McLeod (Member # 33) on 09-27-2003, 03:51 PM:

Also check to make sure there isn't tooo much tensionon the film as it goes through the media

Posted by Dennis Atkinson (Member # 345) on 09-28-2003, 09:11 AM:

How could black lines/scratches show on screen if Film Gaurd is being used correctly? How dirty is the booth!?

Dennis

Posted by John Pytlak (Member # 331) on 09-28-2003, 10:20 AM:

Dennis asked:

quote:
How could black lines/scratches show on screen if Film Gaurd is being used correctly?

A treatment like FilmGuard "hides" scratches by filling them in with a material that has nearly the same optical refractive index as the film, so light isn't scattered by the scratch. But a deep scratch would not be able to be completely filled in, and so will still be visible, although less so.

Same principle as "wet gate printing":

http://www.kodak.com/US/en/motion/support/h1/printingP.shtml#wetgate

Posted by Dennis Atkinson (Member # 345) on 09-28-2003, 02:48 PM:

Thanks John, I knew that.
If the film was being treated and the instructions were followed, black lines would be tough to produce.

Dennis

Posted by Mike Carro (Member # 232) on 09-29-2003, 12:01 AM:

This might be a stretch but... could it be it's not scratched at all but merely those nice little lines of filmguard that show up until you've run the print a few times?

Posted by Greg Mueller (Member # 17) on 09-29-2003, 10:05 AM:

I was just going to say that Mike...
Are you sure these are scratches and not too much Film Guard on the film? On my first run through of a film I always put on a ton of FG because usually the print is pretty crusty when I get it. This CAN give the "look" of having scratches. I always announce to the viewers that I am cleaning the film and these are NOT scratches.

Posted by System Notices (Member # 2357) on 10-10-2004, 03:39 AM:

It has been 376 days since the last post.

Posted by Dominic Espinosa (Member # 2122) on 10-10-2004, 03:39 AM:

I realise this is an old topic but I figured I'd ad my $.02 just for completness.

Unless the film cleaner is one I havn't worked with before the action of the drive roller is perfectly steady the scratches should move.
If the scratches seem to shake back and forth in a smooth pattern from trailers to tail then it's the cleaner, otherwise, if they don't move or barely move it's something else, such as dragging on the edge of your projectors case.

Posted by John Wilson (Member # 269) on 10-10-2004, 10:47 PM:

Did we ever get a resolution to this?

Posted by Kenneth Wuepper (Member # 1174) on 10-12-2004, 07:18 PM:

A possible random cause for base scratches could be the result of improper threading of the platter "dancer rollers". It is possible in a poorly lighted or relatively inaccessable position to thread the film under the locking pin used for threading the platter. It appears that the film is traveling around the roller when it is also scratching on the underside of the release pin. Since this would only scratch the side facing up, soudtrack toward the pillar would cause the base to be scratched at that point.