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Author Topic: Mystery Scratches
Alaina Shaffer
Film Handler

Posts: 1
From: Branson, MO, USA
Registered: Dec 2008


 - posted 12-28-2008 02:49 PM      Profile for Alaina Shaffer   Email Alaina Shaffer   Send New Private Message       Edit/Delete Post 
Hi all who are more experienced than I.

I am having an issue with the projectionists at my theater... They keep scratching movies! I cannot for the life of me figure out what they are doing but this is what _all_ of the scratches look like...

They are traveling vertical down the right side of the screen with mostly black and the occasional green scratch showing through.

At first I thought it was equipment error (when the first two films were scratched on the same projector) but after cleaning every roller and realigning everything the scratches still showed up and then they started to occur on other projectors so now I am leaning towards user error by one of my more full time employees.

Any thoughts as to what might be causing this?

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Bill Gabel
Film God

Posts: 3873
From: Technicolor / Postworks NY, USA
Registered: Jan 2002


 - posted 12-28-2008 02:54 PM      Profile for Bill Gabel   Email Bill Gabel   Send New Private Message       Edit/Delete Post 
What kind of projector and platter system do you have? That is the first question everyone will ask you for the mystery of the scratches.

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007


 - posted 12-28-2008 02:56 PM      Profile for Jeremy Weigel   Email Jeremy Weigel   Send New Private Message       Edit/Delete Post 
Post pics of their threading. This will help us diagnose any errors.

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Tim Reed
Better Projection Pays

Posts: 5246
From: Northampton, PA
Registered: Sep 1999


 - posted 12-28-2008 03:44 PM      Profile for Tim Reed   Author's Homepage     Send New Private Message       Edit/Delete Post 
quote: Alaina Shaffer
after cleaning every roller and realigning everything the scratches still showed up and then they started to occur on other projectors so now I am leaning towards user error
Yep, I'd tend to agree with that assumption. It only takes one mis-thread to ruin a whole print.

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Dominic Espinosa
Phenomenal Film Handler

Posts: 1172
From: Boulder Creek, CA.
Registered: Jan 2004


 - posted 12-29-2008 12:14 PM      Profile for Dominic Espinosa   Email Dominic Espinosa   Send New Private Message       Edit/Delete Post 
Sounds like they're not square on a roller somewhere and are either riding the flange or getting torn up by a keeper roller.

Although that is just a guess...I'd advise spot checking them. Stop by randomly and see what their threading looks like.

See how they thread -- carelessly? Do they check their work?

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Tony Bandiera Jr
Film God

Posts: 3067
From: Moreland Idaho
Registered: Apr 2004


 - posted 12-29-2008 02:26 PM      Profile for Tony Bandiera Jr   Email Tony Bandiera Jr   Send New Private Message       Edit/Delete Post 
Hi Alaina, welcome to Film-Tech, you'll find tons of helpful advice and people here. [Smile]

As I had advised another person in another thread, the best way to get to the bottom of this issue is for you to drop in UNANNOUNCED and tour the booth as each of your operators is on shift. That way you'll see their true habits and find out how your film's getting scratched.

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Lauren Wilson
Film Handler

Posts: 1
From: Mercer Island, WA, USA
Registered: Nov 2008


 - posted 01-04-2009 05:46 PM      Profile for Lauren Wilson   Email Lauren Wilson   Send New Private Message       Edit/Delete Post 
Hi Alaina,

I'm at a new theatre and you're scratches sound exactly the same as the ones we have on all our 18 prints but two. Yet I don't think its operator error, we have christie platter systems and I think the cluster is the route of the problem, numerous cleaning and careful threading has yet to resolve the issue and I'm curious if any one out there has any suggestions.

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Jeremiah Teague
Film Handler

Posts: 17
From: Fort Collins, CO
Registered: Dec 2008


 - posted 01-06-2009 03:29 AM      Profile for Jeremiah Teague   Email Jeremiah Teague   Send New Private Message       Edit/Delete Post 
I have a similar problem. They are always light black on the right side. affects about half of the prints (8). I think it might have something to do with our tension bands or film gate (christi p35gps heads) but I'm not sure. It could be human error as well. Does anyone have ideas on what causes these or scratches in general?

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99


 - posted 01-06-2009 04:08 AM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
How close are they to the right edge of the screen? For example, if your screen is 20 feet wide, are they 2-3 feet in from the right edge?

Can you take a picture of the scratches and post it here? If people can see them, we can narrow it down much faster and more accurately.

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Jeremiah Teague
Film Handler

Posts: 17
From: Fort Collins, CO
Registered: Dec 2008


 - posted 01-06-2009 04:18 PM      Profile for Jeremiah Teague   Email Jeremiah Teague   Send New Private Message       Edit/Delete Post 
I'll try and get a picture on my next shift. The screens are about 50 feet wide and the scratches are like vertical cat-scatches on the right between 1 foot and 4 feet. Our prints are usually fine for the first 2-3 weeks of play and then they will sometimes start to scratch. Usually the longer we have a print, the worse off it'll be. I can't pin it down to a particular projector. It would be multiples anyway.

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99


 - posted 01-07-2009 04:03 AM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
Jeremiah, what kind of failsafes do you have? Also look closely at your pad rollers and tell me if they have the "inner" guide on them that would be resting up against the very inside edge of the sprocket holes. There is also the chance that it is the intermittent shoe, but regardless it will be one of those three things on a P35GPS.

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Jeremiah Teague
Film Handler

Posts: 17
From: Fort Collins, CO
Registered: Dec 2008


 - posted 01-10-2009 04:39 AM      Profile for Jeremiah Teague   Email Jeremiah Teague   Send New Private Message       Edit/Delete Post 
Fail-safes are Component Engineering FM-35. The pad rollers we have do have the guides that rest up against the film. They only touch the sproket-hole area.

The pictures I took didn't capture the scratches so I simulated them on this picture:

(it wouldn't accept my picture, so see below)

The black scratches aren't straight. They usually wave left and right a bit. There are also multiple "lines". A few prints every now and then get green dots.

I also took pictures of my threading and posted them on my picassa site. Let me know if this seems off to anyone.
scratches at picassa

Like I said earlier, it may be human error. What kind of threading mishap could lead to something like this? I've tried purposefully mis-threading trailers to find out, but I can't reproduce this.

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Demetris Thoupis
Phenomenal Film Handler

Posts: 1240
From: Aradippou, Larnaca, Cyprus
Registered: Apr 2001


 - posted 01-10-2009 12:46 PM      Profile for Demetris Thoupis   Email Demetris Thoupis   Send New Private Message       Edit/Delete Post 
It looks like the problem is created during makeup of the film. Do you makeup on spools and then load on the platter or do you load the platter directly? The scratches do not seem to be symetrical so it proposes that the film rubs/drags along the non operator side somewhere. The most usymetrical thing is the spools of makeup (which could be bend) or the platter during makeup which could bump up and down causing film to rub/drag if the roller is not allinged properly. When you have a brand new print, do you have these scratches or are they not apparent until a play or two? Christies although having their flaws treat film quite nicely.
Demetris

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99


 - posted 01-10-2009 02:26 PM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
His simulation isn't buildup scratches. Unfortunately the pictures of the threading are angled straight-on so I can't see what kind of pad rollers are on there.

Regardless, the lower loop is too big. With the lower pad roller open and you turning the projector over slowly by hand, the smallest part of the loop should pull snugly against the open pad roller. Too big of a lower loop can put standing emulsion scratches and/or destroy the SRD track (depending on if you have slap guards installed under the ultramittent or not).

Go into the tips section and look at "threading 101".

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Jeremiah Teague
Film Handler

Posts: 17
From: Fort Collins, CO
Registered: Dec 2008


 - posted 01-10-2009 04:46 PM      Profile for Jeremiah Teague   Email Jeremiah Teague   Send New Private Message       Edit/Delete Post 
Yeah, the scrathces we get aren't from build-up. Every print will look pristine for the first week or 2, but then the scratches appear. We build-up both ways, though. Some from reels to platter and some we build onto big reels and then transfer to the platter.

That's funny that you say my lower loop is too big. I used to thread exactly how you describe and the regional booth tech told me that it was "way too small" and that I was probably "scratching the sh#t out of prints" so I changed the way I did things. Considering you and the head's manual say otherwise, I'll change back.

Thanks, all.

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