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Topic: Shedding problems!

Ron Curran
Jedi Master Film Handler

Posts: 504
From: Springwood NSW Australia
Registered: Feb 2006

posted 04-23-2006 09:17 PM

Some of the GN&GL problems were posted on the Universal and Cyan thread

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-24-2006 01:35 PM

Release prints should be properly edgewaxed, per Kodak's H-24.02 processing specifications and SMPTE Recommended Practice RP 151:

H-24.02 Processing Specifications

quote:
Edge Coat
The 35 mm and 70 mm films for theatrical projectors
need additional waxing for satisfactory projection life.
This additional wax is coated on the film edges since
theatrical projectors require an amount of lubricant
that would cause mottle on the picture area and in the
sound stripe.
The edge coat waxing equipment described by Perry
and Mino is recommended. Variations of these units
can easily be made an integral part of the processing
machine to reduce handling costs and increase the
speed of production. In the basic design, rotating discs
apply the lubricating solution to the area of the film
that lies outside the picture area along the perforations
and edges. These discs usually rotate in a lubricant tray
and they depend on surface wetting to pick up and
transfer the solution to the film. The applicator discs
should be coupled into the main drive to assure that
film speed and applicator speed remain equal.
Wax is usually applied only to the emulsion side of the
film. The drying rate of the edge coat formula should
be low enough to allow transfer of wax to the support
side of the roll. Some laboratories lubricate both sides
of the film directly.

Proper edgewaxing is especially important for B&W silver image prints, as they absorb more heat, and have actual particles of silver in the emulsion.

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Chad M Calpito
Master Film Handler

Posts: 435
From: San Diego, CA
Registered: Apr 2006

posted 04-24-2006 01:40 PM

Last night, while working my closing Booth shift, I noticed that the movie Silent Hill shedds terribly. I contstantly have to clean all of the heads after each show & the movie is in Theatre #10, which is the biggest auditorium. Of course, as we all know, this is a new movie.

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John Hawkinson
Film God

Posts: 2273
From: Cambridge, MA, USA
Registered: Feb 2002

posted 04-24-2006 02:28 PM

I was kind of hoping for a more direct response, John. [Frown]

Maybe
you didn't see my longer post on the previous page?

Is it possible that these prints were misprocessed somehow,
or is it normal to see more damage in the picture area with 2302?

I understand how there'd be more buildup and soforth on the edges and the soundtrack area, especially if shed particles adhere in the trap, etc. But is there a vector that would lead to verticle base-side scratches in the image area?

--jhawk

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Cory Isemann
Jedi Master Film Handler

Posts: 500
From: White Plains, MD, USA
Registered: Jun 2004

posted 04-24-2006 03:40 PM

FWIW, the print I had a couple of months ago had made the rounds, believe me, it was well used. It shedded like crazy and eventually got better after repeated FG treatments.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-25-2006 11:24 AM

To be effective, edgewaxing must leave a wax deposit in the areas of the print most subject to abrasion by the projector gate. History and experience shows that the deposit of paraffin or carnauba wax in the perforation area helps lubricate the surface, reducing abrasion and scratching of the print. Of course, the surface finish, temperature, tension, and design of the film-contacting surfaces of the gate also have a significant effect on how much they may abrade the film.

I would not attribute scratching of the image area to a particular cause, based on limited experience with one print. Ideally, good projection design avoids contact of the image area with anything that may scratch the film.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-25-2006 02:13 PM

quote: John Hawkinson
I wonder, what would it have taken for WIP to have produced 2383 (or 2393) prints of this? While they might not look quite as good pristine, I have to wonder if they would not have held up better, such that a 6-month old print would look a lot better (it could hardly have been worse).

Would it have been necessary to strike new intermediate elements, or could color prints have been made from the existing internegatives? (I see from Kokak's datasheets that 2302 and 2382 have different trim/tape values, esp. that they are uniform for 2302 whereas 2383 has a blue bias.)

Yes, B&W images can be printed onto color print film, as has been done for some features in the past. But it is very difficult to maintain an absolutely neutral B&W image, and a slight tinting is usually visible. So some filmmakers prefer to use "real" silver image prints.

The B&W print film stock is about $0.03 (3 cents) more per foot, and special processing arrangements need to be made when thousands of prints are needed, since most labs have limited B&W processing capacity.

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Carl Martin
Phenomenal Film Handler

Posts: 1424
From: Oakland, CA, USA
Registered: Feb 2002

posted 04-26-2006 03:58 AM

john, can you elaborate on the "special processing arrangements"? are they special because they are inferior (but "necessary" due to the high print demand)? or could it be that these arrangements are typically not made when they should be?

it does seem that large b&w print runs lately have routinely been bad. jhawk's problems mirrored ours with that film. i heard similar stories about "celebrity" several years ago. on the other hand, small runs like "elevator to the gallows" seem fine.

jhawk, we ran nearly every showing of gngl through a media cleaner, and it kicked up quite a duststorm. the side of the cleaner itself became caked with dust, and it seems likely that dust might also have been propelled into the image area, where it could conceivably have caused scratching on subsequent passes.

carl

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Dan Lyons
Jedi Master Film Handler

Posts: 698
From: Seal Beach, CA
Registered: Sep 2002

posted 04-26-2006 04:04 AM

Perhaps it is a problem with your equipment being rough on the film?

I ran "goodnite" for a 7 week run, and it was a USED print. It ran it through media/filmguard for the first 4 shows, then only through the cleaner ONCE A WEEK thereafter. My Century's stayed perfectly clean. [thumbsup]

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John Hawkinson
Film God

Posts: 2273
From: Cambridge, MA, USA
Registered: Feb 2002

posted 04-26-2006 08:12 AM

FWIW, my experience was based on two prints of Good Night, and Good Luck, both damaged in essentially the same way. I realize that's still not statistically significant, but, coupled with the anecdotal comments that I seemed to recall from folks on F-T, it seems awfuly suspicious.

--jhawk

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Scott Norwood
Film God

Posts: 8146
From: Boston, MA. USA (1774.21 miles northeast of Dallas)
Registered: Jun 99

posted 04-26-2006 08:13 AM

We had GN&GL from October until a couple of weeks ago. Aside from a light roller scratch (not my fault), it stayed in excellent condition throughout the run, with no dirt and minimal shedding after the first week or so. No film cleaner, no FG, no PTRs. The SRD track went bad after about a month, however.

Why didn't they print this on acetate-base 5302 (which, as far as I know, is still available, or at least was very recently)? That doesn't seem to shed.

edit: correct product number

[ 04-26-2006, 12:43 PM: Message edited by: Scott Norwood ]

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-26-2006 11:56 AM

The "special processing arrangements" might mean temporarily converting a processing machine from the ECP-2D (color print) process, to the D-97 B&W process. Many labs have only one machine dedicated to B&W, and they usually run quite slow, so an order of over a thousand prints usually requires more B&W processing capacity.

Yes, Kodak sells both acetate (5302) and polyester (2302) versions of B&W print film. Both should be properly edgewaxed, as B&W emulsion needs the added lubrication (due to the issue of added absorption of radiant heat and the presence of actual silver particles in the processed film emulsion). The variability of both edgewaxing and projectors in reducing projector abrasion is seen from the variety of both good and bad experiences mentioned in this thread.

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Carl Martin
Phenomenal Film Handler

Posts: 1424
From: Oakland, CA, USA
Registered: Feb 2002

posted 04-27-2006 03:08 AM

well, our print was used and abraded when we got it, with a gouged out srd track. it would have been interesting to see what would have happened with a new print. many theaters rarely if ever clean out their filmpaths, so any deposits would be left to abrade the film on the next run. when we got the print, it was already leaving huge crusties in the gate after every show. the media on our cleaner would get progressively dirtier and saturate over the course of a show. i'm sure film-guard would have helped. oh well.

carl

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Ian Woloschin
Film Handler

Posts: 54
From: Worcester, MA, USA
Registered: Mar 2006

posted 05-02-2006 09:16 AM

We just ran Good Night and Good Luck Sunday night. I was in the booth for the first showing, but I was busy on the computer, and not paying attention except for changeovers (we're a university as well, no money platters).

We have two Norelco DP70 projectors, entirely stock except for new cyan dye track readers (the Kiniton model made specifically for DP70s).

I did notice the film was somewhat scratched in the image area, but not anymore than other films we've gotten from Swank, though I didn't notice any problems with the audio, except for a funny warbling, but that's one of my projectors not reading the sound track right, not the film.

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Robert Burtcher
Expert Film Handler

Posts: 194
From: Oklahoma City, Oklahoma
Registered: Jun 2005

posted 06-09-2006 07:49 AM

I've got some issues with BAD shedding on another movie, The Break Up. Last night, when I got to the projector to thread up, there was a ton of black dust all over the place, as if someone had taken a jar of ground pepper and dusted it all over the projector. We're out of FilmGuard, but I don't trust our PTR rollers, so I threw the Kelmar media cleaner on with a full roll of dry media and let it dry-clean the film. The pads came out almost totally black the first run. The film continued to shed.

I set the gate band tension on the Cinemeccanica Victoria 5 to the lowest possible setting while still maintaining a steady picture, and ensured that the constant speed sprocket pad roller was properly adjusted away from the sprocket (2 thicknesses of film). Still no improvement.

Anyone else having a similar problem, and/or anyone have any tips for fixing this problem?

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