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  • #16
    My bench cleaning setup and a comparison of the two brackets. One is missing the roller because it’s NOS and I didn’t bother attaching it.
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    This gallery has 3 photos.

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    • #17
      Hopefully, you're using Film-Guard on the cleaning media... Running anything through dry media is risky.

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      • #18
        Most any of them. My experience is more with using it with new film while that was the current medium...less so on collectors prints though one collector swore by it, for sure. He also claimed that it stopped vinegar syndrome. I spoke with someone from Kodak about FG and they found that FG could leach out dyes but didn't give any concrete details on the rate by stock or anything. If you are using FG and notice that after a week or so of use (using the soaked pads on each show) you are seeing green and magenta staining on the pads...where do you think that is coming from?

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        • #19
          Definitively proving if FG (or any other chemical) will slow down VS is near-impossible. That being said I've never told people that it will prevent or stop it, but I have consistently found that it does indeed seem to really slow it down if used pre-VS or at the very beginnings. That being said we do have a system at our lab to outgas VS prints if they aren't too far down the A-D strip road.

          I have prints in my personal collection going back quite literally 35 years with no sign of dye leeching. To use a phrase from Tropic Thunder, Kodak most certainly went "full retard" overboard with it on an extreme test since that's how you have to when testing things. If using the product as instructed, that concern has effectively been debunked a long time ago. I've certainly never seen it in any of my prints, but to more accurately answer your comment, having a discoloration on the pads is something that I have only ever witnessed with a scratched print, but that's not overall dye leeching. As the pads are rewound and re-soaked, it smears on the pads and just looks like general discoloration.

          What was likely happening if you saw that on prints received new was either the pads you were using were slightly abrasive or most likely the back tension was too great from the supply reel. If a print is put through an ultrasonic cleaner with trike or perc, it will totally clean off any hint of FG, but the film will now show if the user had too much back tension as light scratches would then be visible under the light on an inspection (even if they don't project).

          Remember I've always said that a PLATTER is the ideal way to use FilmGuard. That or a "motorized feed" reel to reel system. The reason is because the back tension is absolutely consistent and controllable.

          And here is where my frustration with running reel to reel with a CLUTCH-based feed and rewinder begins.

          With any type of drag clutch (such as on a typical Kelmar rewind bench or an upper reel arm), the tension increases as the film empties from the supply reel. Most reel-to-reel guys have their clutches set too high and with that it's not too difficult to reach a level of pressure against the media to start making scratches, despite the fact that they wouldn't project due to the FG. (The primary reason is because of the projector motor starting too quickly instead of with a slow and constant ramp-up in speed. This causes the feed reel to "yank" the film reel up to speed from a dead stop and then if the clutch isn't set high enough the reel will noticeably over-feed upon starting and spill film outward. The issue is the tension setting to keep the film reel from bouncing is too damn much for running a cleaner, and also too high to prevent cinch scratching from happening.

          Note that anyone running film in 2024 really should have the projector motors on an inverter with a ramp up speed of no less than 5 seconds. That's plenty of time for SRD and/or SDDS to be able to start tracking valid data and it also causes less base side scratches from a sound drum trying to get up to speed.

          Reel to reel houses with clutch-controlled tensions should be following the golden rule of decreasing tension in their wind (regardless of any type of film cleaning that may or may not be occurring there):

          1. Coming out of the projector the tension should be as tight as possible without any possible concern for being so tight that sprocket stretching could happen at the hold back sprocket.

          2. On the rewind table the tension should be a bit less than it was on the projector's takeup. Assuming a typical Kelmar-style of rewind table, the primary concern during rewind is that cinch scratches can still happen on the motorized reel (the one on the right) during rewind due to the constantly increasing tension from the clutch-controlled reel (the one on the left). As far as putting a film cleaner on the rewind bench, it becomes difficult for a Kelmar table to not over-exert back tension on a cleaner since the next step Digital Cinema Forum dictates an even lower tension wind.

          3. Once the film is on the top of the projector, the back tension setting need to be as low as absolutely possible. A little bit of a bounce is not going to hurt anything at the start of the reel, but remember as the feed reel empties, the upper feed arm is actually exerting MORE back tension as the reel empties (just like the left side of that Kelmar rewind table). Also remember the highest tension part of the reel on the projector feed is on the loosest-wound part of the reel from the rewind table! It's why even on a "reel to reel / changeover-only print" that has been ran (sometimes as few as a dozen times) you can tell the reel change is coming on screen from all the cinch scratches before you ever see that motor cue.

          Keep in mind also that many reels have hubs that are "out of round". For example a LOT of 4 inch cores (used in 35mm shipping reels) do not spin true. This causes a constant "loose (slack) > tight (tug) > repeat" repetition with every spin of the reel that will cause cinch scratches on the rewind table as well as projector feed. Similarly a LOT of "Goldberg-type house reels" (35mm and 70mm) have hubs which are simply NOT round or NOT "centered" (spinning true), and the same thing happens. (In the world of 70mm, MOST of the 70mm metal "shipper" reels are blatantly out of round.) All of this is effectively just like tugging on the end of a cored trailer to "tighten it up".

          Another problem are projectionists who use those awful enclosed Goldberg rewinders for 35mm and rewind tables with some sort of "auto-shut off" arm or lever. When those stop they don't "ramp down in speed to a stop". They abruptly STOP! And with that the film slides forward on itself and creates slippage and more of that cinch scratch rain at the end of the reel. (Some rewind tables stop so violently that if the tip of the film is tucked into the slot, this action will force-feed more leader into the center of the hub.)

          To make things worse, short head and tail leaders mean any dirt and dust that is collected from the leaders will quickly migrate into the image part of the roll with each rewind. That dust and dirt on the surface of the film when you have tension winding issues then becomes an abrasive agent that creates all of those cinch scratches all over the image.

          These are also those projectionists who complain when they find long leaders and insist on winding past them to thread (either by dumping the leader on the floor or dragging it across the side of the projector and winding it down onto the takeup reel) so they can "thread on the countdown". This careless practice defeats the purpose and craps up the start of the reel because that handling dirt migrates into the reel a little bit more with each rewind. (Forensic evidence dictates that these projectionists also apparently love fried chicken.)

          But just try and get your typical changeover operator to realize any of that. Most out there these days believe "there is no platter here, so my system is perfect and of archival quality". Uh huh. I especially love when I hear "I went to the 2 day archival projection training seminar at XYZ company, blah, blah, blah so I am an ARCHIVAL CERTIFIED projectionist and know everything!" Another favorite is the silly logic of "we have ran movies like Lawrence of Arabia and 2001 so we are experts". (The problem with any of the projectionists in this group is they will never be great at what they do because they won't listen to better, more logical advice and learn so they can improve their practices. Those fall into the "just want to watch the reels spin" group.)

          It's frustrating because there is no need for film presentations, especially in 2024, to be anything less than flawless, but people have to learn just because they were originally trained to run film a certain way is NOT some sort of absolute best practice. People have to use their heads and acknowledge that "maybe the way I was taught actually isn't the best way to handle film" (yes I know, the concept is shocking) and learn to make some small adjustments to their procedures and equipment checks.

          When a given venue only plays a print a few times before shipping it off to the next venue, they just don't see the slow accumulation of damage that happens a little bit more at each location with poor film handling practices, and as such assume they aren't inflicting any damage (when in fact most of them do).

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          • #20
            The recommendation for setting the take-up tension hasn't changed since the silent era... it should be set to the minimum required to take up a full reel without laboring. The tension will be high enough to cause cinching way before it's high enough to cause perf stressing at the holdback sprocket.

            Originally posted by Brad Miller View Post
            1. Coming out of the projector the tension should be as tight as possible without any possible concern for being so tight that sprocket stretching could happen at the hold back sprocket.

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            • #21
              Jesse that's dead wrong, and again like with so many things, just because some recommendation from 100 years ago was made or "it's how I was taught" is irrelevant. The film is being restrained by the sprocket holes on takeup. During rewind the only restraining is by the physical film itself wound on a reel, and if that pack is able to slip at all, you have cinch scratches. THAT as well as short leaders where people are handling the film too close to the first or last frame of action, is why almost all of these older films have so much wear at the end of the reels. Forget what someone told you or that you read in an old and outdated book. Think about it. Logic is your friend.

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              • #22
                Originally posted by Jesse Crooks View Post
                I have been lucky enough to have NOS parts so I can't recommend an alternative source, but Kelmar is still in business, so why not buy from them? Hopefully they'll continue to do enough business to keep supporting their line of film-related products.

                If the o-rings on the drive wheel are showing signs of wear (ex., cracking) they should definitely be replaced. Same goes for the neoprene tubes on the media pad take-ups. As you say, storing them compressed ruins them faster. I think on all of the ones I've opened the chain drive has had some slack. I would clean off any old lube and add a little bit of SuperLube multi-purpose synthetic to the gears.

                The factor that determines the direction in which you can mount it is the mounting bracket. There are two styles. One is for mounting the cleaner between the projector head and the feed reel arm. It sounds like that might be what you have since you mention wanting to turn them 90 degrees to match the orientation in the video. The other is for mounting the cleaner on a platter tree (autowind bracket, Kelmar part#: 7508229), which is the one in the video. That's the style you'd want for bench cleaning, since it allows you to mount the cleaner with the film path running horizontally (with the cleaner in that orientation, there are holes in the bracket to bolt it DOWN to the table top, whereas the other type of bracket will have the holes on the SIDES).

                If you search the archived forum you'll find photos of Steve Guttag's setup, in which he mounted the autowind cleaner bracket to the mounting bracket for a Neumade frame counter (note that the frame counter bracket does not come with holes that align with the cleaner bracket so you'd have to tap your own). That tilts the cleaner back at the same angle as the spindles so there's no twist in the film path, and allows you to hold it in place using the same screw as the frame counter. No additional mods to the table. If you're going to mount it to a Kelmar table, that's the way to do it.

                A separate hand rewind station will definitely be the easiest option. And I like being able to lower the tension towards the end of the reel. If you use it infrequently you can always disassemble it for storage
                Cheers, the link hunt did reveal these archived threads with some fellow setups photographed:

                Steve's
                http://www.film-tech.com/cgi-bin/ubb...550;p=2#000020

                Randy's
                http://www.film-tech.com/cgi-bin/ubb/f1/t005596/p2.html

                Unfortuantely no neumade frame counter bracket here at this time. Would be nice! We only got the guy floating on the desktop board like this:
                https://www.ebay.com/itm/116101457446

                I'll have to go investigate the old platter tree in cold storage, maybe mounting brackets still remain mounted there. But my other hunch is these were purchased 2nd hand with the intent to mount and then never installed. The projector number masking tapes I removed don't correspond to anything we have (having only 2). Both will need new neoprene sleeves and o-rings at minimum. And obviously it only would require getting one working unless I'm being nice and passing one along to someone.

                Are either of these the suitable model for conversion to bench cleaning?

                IMG_5725.jpgIMG_5726.jpg

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                • #23
                  Originally posted by Brad Miller View Post
                  Another problem are projectionists who use those awful enclosed Goldberg rewinders for 35mm and rewind tables with some sort of "auto-shut off" arm or lever. When those stop they don't "ramp down in speed to a stop". They abruptly STOP! And with that the film slides forward on itself and creates slippage and more of that cinch scratch rain at the end of the reel. (Some rewind tables stop so violently that if the tip of the film is tucked into the slot, this action will force-feed more leader into the center of the hub.)
                  *eyes the equipment in my booth with a renewed sense of disdain and caution*. LOL

                  Other than the abrupt start/stop issues noted... the enclosed goldberg one we have produces a far far better wind than our kelmar bench does. I've often wondered if it would be even better to just put a couple bypass rollers on the projector and just use the projector itself to rewind, especially when aiming for re-shipping back on cores. Our best winds are definitely fresh off the projector, but they are tails out of course.

                  Another local projectionist had mentioned running film backwards through a projector to get a good wind for shipping, but that seems like inviting disaster, or at minimum unnecessary extra wear. (He was at the time working in a now well known nationwide venue, that didn't even have house reels, they rolled off plastic shipping reels, so advice weighted appropriately).

                  If didn't get a good wind for shipping on cores, what is the best remedy... run it forward and backward a couple more times to approach a flatter wind (assuming you do so with a ramp up/down on a bench that isn't over-tensioned?

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                  • #24
                    Aside, one of our recent 70mm prints had a full 3in "fold back" onto itself mid reel found during pre-inspection. We were scratching our heads as to "how does this even happen"? But Brad's cautions about rewinders that perform the abrupt stop.... now I think I understand how it happened. If there was a tension variation anywhere in the reel, the abrupt stoppage would cause all that mass to want to carry on around... and it did, folding the film back on itself mid reel. Yikes.

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                    • #25
                      I don't know if there are any substantive differences with the Christie badged version, but it looks about the same. You mount it on the bracket so the holes go over the roll pins, and then tighten the captive screw (looks like the screw itself is missing from the Christie). There are some slight difference in the face plate (see the recessed hex screws and what look like holes for small roll pins on the bottom of the Christie). Hopefully someone who has used both can tell you if they fit the same bracket.

                      Originally posted by Ryan Gallagher View Post
                      Are either of these the suitable model for conversion to bench cleaning?
                      Last edited by Jesse Crooks; 09-09-2024, 10:02 PM.

                      Comment


                      • #26
                        Logic (and every reliable source I've ever heard from) tell me that the lowest tension required is always the correct amount of tension. With the take-up set to the minimum required to take up a full reel, I always get a nice, tightly packed, even wind. No slipping. I seen no difference between the wind I get on reels that have been taken up on Kelmar reel arms I've calibrated this way and my E series Kinotons.

                        This is not a controversial position. Everyone from F. H. Richardson to the Kelmar will tell you the same thing. According to the Kelmar reel arm installation instructions: "Take-up clutch pressure should be just enough to ensure uniform and consistent wrap of the film on a full reel. Excessive pressure will encourage under-cutting of the holdback sprocket and introduce undesirable deformation and abrasion of the film."

                        Originally posted by Brad Miller View Post
                        Jesse that's dead wrong, and again like with so many things, just because some recommendation from 100 years ago was made or "it's how I was taught" is irrelevant. The film is being restrained by the sprocket holes on takeup. During rewind the only restraining is by the physical film itself wound on a reel, and if that pack is able to slip at all, you have cinch scratches. THAT as well as short leaders where people are handling the film too close to the first or last frame of action, is why almost all of these older films have so much wear at the end of the reels. Forget what someone told you or that you read in an old and outdated book. Think about it. Logic is your friend.

                        Comment


                        • #27
                          Originally posted by Ryan Gallagher View Post
                          Aside, one of our recent 70mm prints had a full 3in "fold back" onto itself mid reel found during pre-inspection. We were scratching our heads as to "how does this even happen"? But Brad's cautions about rewinders that perform the abrupt stop.... now I think I understand how it happened. If there was a tension variation anywhere in the reel, the abrupt stoppage would cause all that mass to want to carry on around... and it did, folding the film back on itself mid reel. Yikes.
                          on 2nd thought, the more likely scenario is maybe a reel flange pinch that went by un-monitored/detected during rewind and cleared itself (by folding the previous pass)?

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                          • #28
                            What's wrong with the wind you're getting with the Kelmar table? That's worth some investigation before you try to develop an alternative. Is the tension set correctly? Could there be an issue with the clutch or the take-up? Are the spindles bent? Are you having issues all the time, or could it just be an issue with specific prints rather than with your table?

                            They're workhorses but do require maintenance. The felt pads need to be replaced with some regularity. At longer intervals the clutch plates wear down. Belt wear and alignment can be an issue. The wiper brush for the variac and the motor brushes will eventually wear down. I've had to replace the bearings on three different feed heads in the last couple years, and most of the tables in service are probably as old or older than mine.

                            Clutch issues are easiest to detect by taking an empty reel and slowing spinning it. Does it turn evenly, or does it drag at certain points in the rotation? The take-up issues I've experienced have been most noticeable at low speed. The film might bob, or power might cut out periodically, etc.

                            If the table is working correctly but you're having trouble with a specific print (usually acetate that's beginning to experience structural issues) there are a few things you can try:
                            • Wind it onto a split reel before winding it onto the shipping reel. Split reels allow the least lateral movement (less room to wander because the flanges are closer together) and when you feed from the split reel to the shipping it will register against the inboard flange of the shipping reel, giving you a smoother wind. You don't want this lateral offset between reels to be extreme, but the difference you get between standard reel types is fine. If it shipped on cores, even better. Running between two split reels will always get you the smoothest wind when the film is misbehaving.
                            • Try inverting the emulsion orientation. Some reels will wind terribly in one orientation and perfectly in another. Obviously you should aim to return prints as received or as specified by the lender when possible, but preventing damage in shipping is far more important. Just notify them and tell them why you had to return it that way.
                            • For really bad prints, using the auto-wind roller can help you get a good wind. Don't go crazy with it (run it a responsible speed and don't actually walk away from it). Just use the roller to give you a steadier wind.
                            In terms of using the projector to rewind for return shipping, that sounds like a lot of trouble to do something the wrong way. If you have a problem with the Kelmar table just do it the old fashioned away and rewind by hand. It will take half the time of running it through the projector, without the risk and additional wear.

                            Projecting onto shipping reels should be avoided for a number of reasons, and I'm guessing that if you're running 70mm rep titles you're probably running archival prints. If so, the lending agreements usually expressly forbid projecting on shipping reels. I would particularly avoid using the projectors for rewinding if you're taking up on cores, since your clutch tension will be too high for the 2-3" hubs that prints commonly ship on.

                            Move the Goldberg to the lobby... it's only good as a display piece. Or a boat anchor.

                            Originally posted by Ryan Gallagher View Post

                            *eyes the equipment in my booth with a renewed sense of disdain and caution*. LOL

                            Other than the abrupt start/stop issues noted... the enclosed goldberg one we have produces a far far better wind than our kelmar bench does. I've often wondered if it would be even better to just put a couple bypass rollers on the projector and just use the projector itself to rewind, especially when aiming for re-shipping back on cores. Our best winds are definitely fresh off the projector, but they are tails out of course.

                            Another local projectionist had mentioned running film backwards through a projector to get a good wind for shipping, but that seems like inviting disaster, or at minimum unnecessary extra wear. (He was at the time working in a now well known nationwide venue, that didn't even have house reels, they rolled off plastic shipping reels, so advice weighted appropriately).

                            If didn't get a good wind for shipping on cores, what is the best remedy... run it forward and backward a couple more times to approach a flatter wind (assuming you do so with a ramp up/down on a bench that isn't over-tensioned?

                            Comment


                            • #29
                              I've seen film fold back like that itself on its own, but only when building up acetate that's getting vinegary or otherwise having significant structural issues up to large reels. The larger the diameter, the lower the curvature, and you see more issues with edge wave, etc., manifest between the layers of film. You start seeing gaps because the film won't lie flat, and it can slip exactly as you describe. You slow down and the outer ring wants to keep spinning. You get an S where the film folded over on itself. I have a hard time imagining this happening to film in good condition though.

                              Originally posted by Ryan Gallagher View Post

                              on 2nd thought, the more likely scenario is maybe a reel flange pinch that went by un-monitored/detected during rewind and cleared itself (by folding the previous pass)?

                              Comment


                              • #30
                                Originally posted by Jesse Crooks View Post
                                Logic (and every reliable source I've ever heard from) tell me that the lowest tension required is always the correct amount of tension. With the take-up set to the minimum required to take up a full reel, I always get a nice, tightly packed, even wind. No slipping. I seen no difference between the wind I get on reels that have been taken up on Kelmar reel arms I've calibrated this way and my E series Kinotons.

                                This is not a controversial position. Everyone from F. H. Richardson to the Kelmar will tell you the same thing. According to the Kelmar reel arm installation instructions: "Take-up clutch pressure should be just enough to ensure uniform and consistent wrap of the film on a full reel. Excessive pressure will encourage under-cutting of the holdback sprocket and introduce undesirable deformation and abrasion of the film."


                                We clearly have a bit of communication difficulty here. You are twisting what I wrote as if I want the film and sprockets destroyed upon takeup. I was trying to elaborate to explain the varying differences in backtension as the film is rewound or fed into the projector, but apparently I did a poor job at composing my response and it just confused things into misinterpretation. So instead, forget all of the more nitpicky details and just understand the core point in the simplest form with this simplified version:

                                Whatever the takeup tension of the projector is, the rewind tension must be lower than that takeup tension, and then the next show's feed tension must be lower than the rewind tension. The sprocket holdback on the projector makes it so you can increase winding tension. That isn't possible on rewind and feed, and if the rewind or feed exerts more backtension...you get cinch scratches, period. It doesn't get more simpler than that, and it's an absolute fact.

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