Film-Tech Forum ARCHIVE: Extremely unusual print shedding

This is topic Extremely unusual print shedding in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=006235

Posted by Ken Lackner (Member # 1002) on 05-31-2004, 09:56 PM:

Simplex 1060 with 5 Star soundhead
Christie AW3 platter

The last few days, one of our prints of The Day After Tomorrow has been shedding in the projector like I have never seen before. It's not a fine dust like most shedding. The particles are more like flakes. They are light pink in color, and they are everywhere in the projector and soundead. They're even near the guide posts on the brain. I have thoroughly checked and cleaned the film path. All rollers are turning freely. The gate tension is set at 2, whcih is lower than most of our other projectors. Any idea what could be causing this?

I have thought of the intermittent shoe tension. I know how to adjust it on a Millenium, but not a 1060. Is it adjustable? If so, how should it be properly set?

Could the type of film stock have something to do with this? Anyone know what type of stock was used for Day After Tomorrow?

BTW, even Film-Guard (applied with a Kelmar cleaner, not just wiping on with a rag) was powerless to stop this shedding. You should have seen the media after one pass! Wish I cad a camera.

Posted by Brad Miller (Member # 2) on 05-31-2004, 10:45 PM:

Zero problems here. I can virtually guarantee you that you have something abrasive in the film path on that screen. Has anyone been jacking around with the equipment recently?

Also, 2 on one projector doesn't necessarily equal 2 on another (gate tension).

Posted by Ken Lackner (Member # 1002) on 05-31-2004, 10:51 PM:

If someone has been messing around with the equipment, I sure don't know about it. As I said, I've inspected the entire film path, but I will again. Any ideas what I should be looking for?

Posted by Dean Kollet (Member # 1789) on 06-01-2004, 12:45 AM:

no problems here either....
I've used the same projector, and if someone were to drop that film gate, the metal that comes in contact with the film could get a slight burr or something, that might increase film shedding. Also, are all of your sprockets good? Sometimes a worn down tooth or two causes the print to shed (it has on me before...)

Posted by Rick Long Jr (Member # 541) on 06-01-2004, 06:44 AM:

Early 1060's didn't really have any way of adjusting the intermittent shoe other than bending the tang. (not reccomended) Later models had a somewhat adjustable and replaceable tang attached to the bottom of the trap with two allen screws. These projectors seem to eat intermittent sprockets. I'd check that. as well the gate lateral guide roller could be loose or out of adjustment. I recently worked on one of these where this roller was so badly out of position that it was shaving the edge if the film, leaving a nasty buildup of pink threadlike fluff. The lower padrollers (and the one on the 5-star sprocket) constantly go out of alignment if the operators are rough on them, and will damage film. If you have time, try running a brand new trailer or something and stop it halfway. then examine everything very carefully. This may help pinpoint the cause.

Posted by John Pytlak (Member # 331) on 06-01-2004, 02:30 PM:

I agree, it sounds like a severe projector abrasion or guiding issue. Magenta-colored debris that is larger flakes or skivings tends to be mostly from the emulsion side or edges of the film. If the debris dissolves in a bit of household hypochlorite laundry bleach (Clorox), it is most likely gelatin. Polyester base is impervious to most solvents and will not dissolve.

Posted by Ken Lackner (Member # 1002) on 06-01-2004, 05:08 PM:

I will check the above suggestions. But I'm still really curious why the particles are flakes. All shedding I've seen prior to this was dust. And It's not magenta in color. It's very very light pink. (I could be mistaken, but would describe magenta as more of a purple than pink.)

Posted by John Pytlak (Member # 331) on 06-01-2004, 05:29 PM:

The top imaging layer in print film is the magenta layer, protected by a clear gelatin overcoat. The edges and area between the perforations receive the most wear from the film-contacting parts of the projector and transport, and they are normally either clear or just contain the SDDS (cyan dye exposure only) or Dolby Digital tracks. So any emulsion flakes are typically a mix of the clear overcoat and maybe a little bit of magenta coloration.

Posted by Thomas Procyk (Member # 1170) on 06-01-2004, 06:12 PM:

Had this same problem not too long ago on a Cinemeccanica V5. Purple flakes everywhere! But they were only very heavy when someone other than me threaed. Dunno how the others do it, but I guess they were overlooking that the intemittent pad roller was out of alignment (for reasons unknown) and was pinching the edge of the film ever so slightly. Slight enough to cause plastic purple flakes everywhere. And black snow on the image, too. [Frown]

Ran FG on that print after it happened, and SHEETS of that purple stuff came off. Took a couple passes, then the print was fine (as long as people threaded it right.)

What you could have is someone misthreaded ONCE, shaved the print, and now the flakes are shaking off the film in your projector pass after pass. FG the crap out of that print! [Big Grin]

=TMP=

Posted by Peter Mork (Member # 1336) on 06-01-2004, 06:16 PM:

Ken, I feel for ya. This is the sort of problem that can be very hard to trace the cause of. All the suggestions made here are good, but it can be extremely tough to play Sherlock Holmes and arrest the actual culprit.

I run an old Brenkert that, every so often, shaves off emulsion from the SR-D area ('tween the perfs). Doesn't happen on every print. We run analogue sound, so the presentation isn't affected, but still, anyone else trying to run digital would find this print a lost cause.

I have gone nutzoid trying to stop this. No burrs in the film path, no worn sprockets, gate tension low, everythin' I can think of hunky-dory - yet this happens. Fooey.

I figure IF I could shrink myself doen to 1-inch size, slow down time, and have x-ray vision to see through metal, I MIGHT have a shot at solving this. Otherwise...

Good luck anyways.

Posted by Joe Redifer (Member # 3) on 06-01-2004, 06:37 PM:

Make a loop from a trailer or something expendable that has ZERO marks on it anywhere. Run this loop in the projector for a good 20 or so. Take the loop out and look at it carefully. Do you see any new abrasions in the film? If so, the location of the abrasions will point you in the direction to look in the projector.[av=k]