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This topic comprises 2 pages: 1 2
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Author
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Topic: Problems, not sure why.
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Brent Arnold
Film Handler
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Posts: 20
From: Grapevine, TX, USA
Registered: Feb 2002
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posted 07-05-2002 11:48 PM
Tonight I showed Doctor Zhivago, everyone left happy though I deffinently didnt.The film is long, over 3 hours, after about 2 hours into the movie, the loop after the intermitent dissapeared, and then the extra slack went on the the other side of the next roller. Also, the roller at the bottom of the projector, before going to the platter came off of alignment, so the film was going against bare metal. It wasnt emulsion side, and the film was running, so I decided I would keep it rolling. Then after aboutt 10-15 minutes of that, the film was constantly going in and out of focus, usually the focus knob would fix it, but then the last time I had to focus it... the focus knob didnt, I couldnt turn the focus knob anymore, so I decided I would losen the lens, and pull it out ever so slightly, so that fixed it, eventually. Then as fate would have it, there was no tension up to the platter, boom failsafe took in to effect, and then the projector went off (as expeccted). But I am wondering what caused the loop to "shift" like that, I believe it was right at a splice, and if not right at, right around... but at it would make more sense. So what could of caused this overall problem, and what could I do to prevent this in the future. What it almost looked like was that it came off the sprockets on the sprocket after the intermitent, but then why did it run the first couple hours fine? (BTW I have an old century projector, I believe a JJ) Thank you so much, I know I have had lots of questions recently, but, hey, thats how I learn I guess. Thank You. Brent Arnold
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Brent Arnold
Film Handler
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Posts: 20
From: Grapevine, TX, USA
Registered: Feb 2002
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posted 07-06-2002 12:04 AM
A little smudge never hurt anyone!But the thing is I did a pre-screening (for myself) to make sure it was fine... and it was. So that is why a bad splice seems kind of out of the question. But I didnt clean the gate between this showing but I cleaned it not too long ago (maybe 2 other films ran through it) How do I adjust the pad roller clearance.
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Leo Enticknap
Film God
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Posts: 7474
From: Loma Linda, CA
Registered: Jul 2000
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posted 07-06-2002 10:39 AM
If this is an older triacetate print then the stock will be more brittle than modern stock. This will exacerbate any perforation damage, i.e. the slightest torn, nicked, stretched or otherwise deformed perforation could get caught in a sprocket tooth resulting in a loop being lost.You need to be really anal in checking for perf damage in an older print. The odd perf can probably be taped over, but for any sustained damage, operate an 'if in doubt, cut it out' policy. Also, some projectors are more tolerant than others of perf damage, and I guess you'll gradually get used to what you can get away with and what not. For example, an FP-20 is extremely kind, and in my experience will run a print that ought not to be showable. A GK-37, on the other hand, is very unforgiving - the slightest perf damage will cause a snarl-up, and anything other than a perfect join will break under the pressure from the sound lay-on rollers (they're similar to the pinch rollers on a Dolby CAT700 digital pickup, only the pressure is much higher). I've never used a Century JJ and so could not comment.
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Paul G. Thompson
The Weenie Man
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Posts: 4718
From: Mount Vernon WA USA
Registered: Nov 2000
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posted 07-06-2002 07:50 PM
I also think you hit a bad or otherwise crappy splice, or some ripped out sprocket perfs. Some people splice over the splicing tape, and sometimes those splices will derail because they are too thick and won't flex enough when passing through rollers and traps. Upon passing through the gate, the gate tension may a little tighter than normal, causing the intermittant sprocket to strip out or severely strain and damage a batch of sprocket perfs on the film.I ran across one just the other week where someone used a hunk of splicing tape and just wrapped it around the film. No sprocket holes or nothing! Supposedly, it was a "repair of an out-of-frame" splice from the previous night's screening, and I didn't check it before I ran it. Result was I had a shut-down. Needless to say, the Simplex XL didn't like that splice. It popped two pad rollers, and derailed itself in the soundhead. The only machine I know of that would handle something like that would be an old Brenkert. ![](http://www.film-tech.com/ubb/smile.gif) Brenkerts Rule!
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John Pytlak
Film God
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Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000
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posted 07-07-2002 06:48 AM
Brent Arnold said: "...the loop after the intermitent dissapeared, and then the extra slack went on the the other side of the next roller. Also, the roller at the bottom of the projector, before going to the platter came off of alignment, so the film was going against bare metal. It wasnt emulsion side, and the film was running, so I decided I would keep it rolling."I know you felt that "the show must go on". But this is one of those cases where "Film Done Right" would say you stop the projector, correct the lost loop, and recheck the film path. The film "going against bare metal" probably left permanent base-side (black) scratches on the print. If it makes you feel better, I once had a splice break just prior to the take-up reel early in one of the reels of GWTW, and found a few minutes of film spilling onto the floor. Rather than interrupt the show for a few minutes to put the film on a new takeup reel, I ran the entire reel onto the dirty floor of the drive-in booth. Using proper technique, I was able to wind the "spaghetti" back onto a reel without tangling or causing additional film damage. But I still feel guilty for getting the reel dirty by not doing "the right thing". (These were the ancient days before good film cleaners). ------------------ John P. Pytlak, Senior Technical Specialist Worldwide Technical Services, Entertainment Imaging Research Labs, Building 69, Room 7525A Rochester, New York, 14650-1922 USA Tel: +1 585 477 5325 Cell: +1 585 781 4036 Fax: +1 585 722 7243 e-mail: john.pytlak@kodak.com Web site: http://www.kodak.com/go/motion
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Paul G. Thompson
The Weenie Man
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Posts: 4718
From: Mount Vernon WA USA
Registered: Nov 2000
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posted 07-07-2002 02:27 PM
Peter:Side weave on the Brenkerts will happen because all the gate parts are finally worn out after 50 years. Replace the slides, guides and refurbish the the film gate lateral guide roller and set them to spec, and that problem will go away for another 50 years. ![](http://www.film-tech.com/ubb/smile.gif) Porno houses and drive-in's liked the Brenkerts. You should have seen some of the crap I had to run through mine at the drive-in.... ![](http://www.film-tech.com/ubb/smile.gif) I think the Brenkerts and Motiographs are the only machines that would pass an 8-inch piece of film without any sprocket perfs whatsoever on one side without jumping out of frame or spitting the film out. Does the old Carbon-Arc screening room in Seattle still run Motiographs?
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