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Author Topic: Weird Scratched Prints Mark J. Marshall Film God Posts: 3188 From: New Castle, DE, USA Registered: Aug 2002 posted 06-16-2005 10:07 PM                    Thanks, John. That helps to explain why we recently had an emulsion side scratch that was solid black during really bright scenes, and very very slightly green during dark scenes.  |  IP: Logged Kevin Raisler Film Handler Posts: 52 From: Warsaw, IN, USA Registered: Jun 2003 posted 06-17-2005 03:14 PM                    If you use basement sound readers? check the rubber or felt pad on the lateral guide for dirt and contamination these can cause the problems you are describing. After each show the tail of the film ends up on the floor thus picking up dirt then next show you get the dirt deposited on the lateral. hope this helps  |  IP: Logged Jason M Miller Master Film Handler Posts: 284 From: Kalamazoo, Michigan, USA Registered: Jul 2004 posted 06-18-2005 05:47 PM                     quote: Jason Miller I still think someone threaded over a keeper roller. I really dont see this, can you please draw me a diagram and show me how this can happen  |  IP: Logged Jason Miller Expert Film Handler Posts: 241 From: Little Rock, AR, Registered: Mar 2004 posted 06-18-2005 05:59 PM                    does that make sense? I'm no artist. usually the roller at the very bottom of the tree or rollers on the takeup assembly (yo-yo) are the culprits.  |  IP: Logged Jason Greek Film Handler Posts: 21 From: Bridgewater, Nova Scotia, Canada Registered: May 2005 posted 06-19-2005 08:02 PM                     We use Strong/Potts Platters, the positioning of your scratches, and that they SEEM to be base, I would look at the final swivel roller the film passes through when rewinding to the platter. we had a few that were adjusted just a touch too low and they were on rarely used platters (we have a habit of not using our bottom ones). the result was base scratches toward that side of the screen and sometimes that close to the centre. the problem happened so intermittently that it took us awhile to figure out what was happening. Try rewinding film on each platter of the two machines and watch the film as it rewinds...  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: California, U.S.A. Registered: Jan 2004 posted 06-20-2005 12:18 PM                     The diagram posted above shows one possible misthread. There's also the possibility that it's on the roller but not all the way in riding on the flange being pinched down by the keeper roller. Though I would think that would cause scratches on both sides...One from the roller flange and done from the keeper. I've seeb scratches very similar to that on AW3's when someone screwed up the brain and had a big bubble of film dragging it down between the trailing and center rollers.  |  IP: Logged Jason M Miller Master Film Handler Posts: 284 From: Kalamazoo, Michigan, USA Registered: Jul 2004 posted 06-21-2005 07:27 PM                     Jason Greek: If the film was hitting the platter wouldn't the scratches be horizontal not vertical?  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-21-2005 11:32 PM                     If the film was dragging against the edge of the platter as it rewound you would get diagonal scratches. It would look like a meteor shower on the screen. (Some people, I have heard, use the analogy of trying to watch the movie through a chain link fence.) Assuming that you wind your platter soundtrack UP and toward the tree: If the scratches are on the base side the scraping is probably happening on the rewind deck. If the scratches are on the emulsion side the scraping is probably happening on the underside of the deck above the payout. These scratches may or may not be diagonal. If the deck above is idle they could be straight lines. If the deck above is also the rewind deck then they could be diagonal. You're telling us that the scratches are mostly straight and vertical. That tells me that the scratching is happening somewhere else. I'm going to vote with the consensus. The scratches are probably from a mishtread at one of the rollers on the platter. Here is one of the most famous ways to scratch film on a Strong/Potts platter: When threading the TOP takeup deck, if you follow the green film path everything will be OK. But if you follow the orange path you are likely to get scratching against the red keeper roller. If you always thread the soundtrack toward the tree so as to get the soundtrack UP then the scratches are likely to be on the base side of the film. If the middle or bottom deck is your takeup and you thread the green path you will also get scratching in a similar location but it's probably not going to be on the base side of the film, but on the emulsion instead. A misthread like this could very well produce the scratches you describe. Try taking an old, useless scrap of film about 6 feet long and painting a section of it, all over, with a dry erase marker. Thread it up along that section of the platter with your "telltale" film. Run it back and forth by hand a few times then look at it to see if the rollers have rubbed some of the dry erase off the film. Thread the film the right way and the wrong way. If you can reproduce the pattern of scratches on the film you have likely found the cause of the problem.  |  IP: Logged Jason Greek Film Handler Posts: 21 From: Bridgewater, Nova Scotia, Canada Registered: May 2005 posted 06-23-2005 12:56 PM                     I thought the same thing, that the scratches should be diagonal, but We've been getting scratches that are vertical, on the left hand side of the screen, base side, and after we adjusted the final rewind roller, the problem disappeared...  |  IP: Logged Edward Cox Film Handler Posts: 2 From: Windsor, ON, Canada Registered: Aug 2005 posted 08-12-2005 08:47 PM                       Reading this topic is what made me decide to register at this forum... this is something that I noticed happen with a Century/Strong combo... if the sounddrum in the projector head itself is not spinning properly, it can cause scratches much like the ones you described. The drum will not spin constantly, so the scratches can come and go. More over, the film path can be perfectly threaded... not missing a single thing. A quick way to check this is to try to spin the sounddrum with your hand... just a light amount of force from your hand should make it spin for quite a while... If it doesn't spin easily, a quick solution that can buy you some time... get a can of WD-40, and just behind the sounddrum, there should be two holes, almost on top of each other. Spray a little amount in the top hole, then check it by spinning it. Now, spray a TINY bit in the bottom hold, and check it again. PS... hopefully, the problem is no longer even a problem for you, but, this is still something to keep an eye out for in the future.  |  IP: Logged Richard Hamilton Phenomenal Film Handler Posts: 1341 From: Evansville, Indiana Registered: Jan 2000 posted 08-13-2005 02:35 AM                     Randy, I understand your drawing and explanation, but I have a hard time seeing how that mis thread could scratch the middle of the image. I agree, the source of the scratch can be tricky to find, but a little troubleshooting skills with time and patience should find it! It is also helpful to know and be able to identify the base or emulsion side of the film. Edward, why is a Century projector/Strong platter combo bad? Does the platter effect the rotation of the sound drum?  |  IP: Logged Adam Martin I'm not even gonna point out the irony. Posts: 3686 From: Dallas, TX Registered: Nov 2000 posted 08-13-2005 12:42 PM                     quote: Edward Cox a quick solution that can buy you some time... get a can of WD-40 NO NO NO NO NO NO NO NO NO! WD-40 is a solvent, not a lubricant!  |  IP: Logged Dan Lyons Jedi Master Film Handler Posts: 698 From: Seal Beach, CA Registered: Sep 2002 posted 08-13-2005 01:57 PM                     quote: Century/Strong combo... if the sounddrum in the projector head itself is not spinning properly, it can cause scratches much like the ones you described. The drum will not spin constantly, so the scratches can come and go........get a can of WD-40 Sounds like you've got bad bearings. Replace them right away.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 08-13-2005 02:42 PM                     Guys, he did say... quote: Edward Cox If it doesn't spin easily, a quick solution that can buy you some time I have had to do exactly this in the past on a frozen sounddrum, and indeed it did buy me the two days it took to get new bearings delivered and installed. I am not advocating this as a "permanent fix" (because it won't be), but yes it will work as a "temporary fix" to buy you a couple of days until you can get the replacement bearings. Would you rather the sounddrum sit stationary and scratch the film? That's the way I interpreted his post. If in reality he was suggesting that WD40 can buy you some time in terms of weeks or months, then by all means no.  |  IP: Logged Mark J. Marshall Film God Posts: 3188 From: New Castle, DE, USA Registered: Aug 2002 posted 08-14-2005 12:38 PM                    What happens to the film if the WD40 gets on it?  |  IP: Logged

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