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  • #16
    I had a mess like Mark G posted about in an Arthouse Cinema I did monthly sessions for a Film Society group. Just got the 35mm Ballantyne rolling from a Speco platter system and got called aside by the group President regarding another issue and after about 8 minutes of talking looked across as the palter horrified to see the takeup plate as NOT moving.
    Hurridely shut the show down and very carefully powered up the take-up platter from the Make Up table speed control and slowly wound the almost 1000 feet of film on the floor onto the platter and then resumed the session with BOTh platters running OK.
    I got caught by the Take Up YoYo dropping right down and thus switching the platter Off as the projector raced away as the Ballantyne there tended to do..lesson well learnt..never got caught again.

    In my early days the guys who trained me always said that IF the reel to reel take-up belt fails just let in all spill out over the floor and NEVER touch it. When the reel ends get hold of the Tail of the film and with someone guiding the route over to the rewind bench slowly wind the film back onto a reel. If you had NOT disturbed the pile it would always rewind neatly back.IF you had messed with it it would be a hell of a job.

    IF I ever lost the guts out of a cored film I would put the 2 bits carefully onto a clean surface, carefully cut the film on a frame line as close to the core as possible, Then take out about 4-5M of film from the larger section again cutting on the frame line with a splicer.Then the outer section was reduced enough to easily slip over the core section, put it into a split reel and slowly wind the film through onto another reel. When the second cut comes along re-splice the cutout section in and wind that onto the reel and when the next cut come along splice that back to the core section and either continue onto the reel or swap things around and wind it all back onto the core from which it had slipped.
    Takes a bit of care but easily done.

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    • #17
      Originally posted by Lindsay Morris View Post
      ...I got caught by the Take Up YoYo dropping right down and thus switching the platter Off as the projector raced away...
      The SPECO platters at my home theater in Erie did not have that cutoff switch and, as long as you ensured that the yo-yo was at the top section of its travel before you started the projector, there would almost never be a problem. If the yo-yo ever does bottom out, you need to check your platter's speed calibration. It should never bottom out if the projector and patter are both working correctly.

      When I got the job of technician, several of my theaters had SPECO platters with that cutoff switch installed and almost every one of them had the same problem as you at one time or another. I just got fed up and disabled them all.

      I remember calling up my boss, one time, and telling him about the problem and his reply was, "Just disconnect the damn things." My answer was, "Good! 'Cause I already did!"

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      • #18
        I had a Strong platter where I had to give the takeup platter a spin by hand when starting the movie if I had two features on the same platter. After it started spinning it was fine but it didn't have the oomph to start up quickly enough with the weight of two features on it. A single feature wasn't any problem, though.

        Those were the days when the movie companies allowed me to have two different movies on the same week so I could have 7pm and 9pm shows. Now I just have one show per night instead.

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        • #19
          Randy, The normal practice was to wind the TU platter until the Yo Yo was at the top of the travel after threading up but I had obviously stuffed up as it must have been well down the spiral screw when I started the Projector so the sudden loose film let the Yo Yo hit bottom and stop the platter.
          Both units worked well together but the Ballantyne was VERY quick off the mark when switched on and as it was Not my gear I just learned to live with that and accept one had to ensure the Yo Yo was at the top of its travel and all was fine then...NO issues.

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          • #20
            On the platters I used, there was a long, skinny bayonet attached to the yo-yo which would activate a micro switch at the bottom of the tree when it went too far down. The idea was good, in theory, but didn't work in everyday use. If the micro switch had been connected to the projectors failsafe cutoff, maybe it would have been better but, then, it might have caused the theater to go dark on a false alarm.

            I tinkered with them for a while and got them to sort of work but, in the end, I got fed up and took them all off. I found it better to just make sure that the platters were properly calibrated and teach my operators how to do things right.

            Yes, some projectors like Ballantyne have fast startups and, yes, you might have to give the platters a push to be sure they get up to speed. Calibrating the platter speed by twisting the Variac shaft in its coupling until its slowest and fastest speeds are in the range you need them to be will help alleviate most of the problems with sudden changes in projector speed. Done right, you should only need to "help" the platters when there is a large, heavy print being played.

            Yes, you really need to be sure that the yo-yo is near the top of its travel before starting the movie. Also, keeping the two guide rods and the spiral rod that turns the Variac clean is key to keeping SPECO platters running well. A very light coating of lube helps, too. Not too much or else the lube will gum up and attract dirt and dust, making the system run worse. I found that two or three sprays of FilmGuard on a clean cloth then wiping the guide rods worked nicely. A couple of squirts on a cloth should be enough to clean the rods on two or three platters. After the rods were lubed with FilmGuard, an occasional wipe-down with just a clean, dry cloth would keep them in good, clean condition for a while.

            If you make sure that you wipe down those rods as part of your regular cleaning schedule, you probably won't need to use any lube, at all.

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            • #21
              Originally posted by Lindsay Morris
              In my early days the guys who trained me always said that IF the reel to reel take-up belt fails just let in all spill out over the floor and NEVER touch it. When the reel ends get hold of the Tail of the film and with someone guiding the route over to the rewind bench slowly wind the film back onto a reel. If you had NOT disturbed the pile it would always rewind neatly back.IF you had messed with it it would be a hell of a job.
              I was given the same advice at the same stage in my career, and later found out the hard way that it works well with acetate but less so with polyester: if the layers get statically charged and stick to each other, base to base, then you can pull multiple layers when rewinding, resulting in a tangle.

              Originally posted by Randy Stankey
              Yes, some projectors like Ballantyne have fast startups...
              One of things I liked about the Kinoton ST-200 was its hybrid approach to the start speed of the feed platter: there was a base speed that ramped up almost instantaneously when the projector motor was started, and speed increases from there were controlled by the feeder arm on the brain. So you never had a situation whereby it was trying to go from a standing start to 30 RPM ish with Titanic on the deck in a second or two, which is basically a recipe for a wrap. The down side is that the Kinoton was electronically and mechanically quite complicated, requiring an interlock with the projector, a rheostat in the control unit, and significant skill to tune up such that it ran nicely. But when it was tuned up properly, the Kinoton was the most reliable and film friendly platter I've ever used.

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              • #22
                I used a Kinoton platter at the Tom Ridge Center. It almost seemed like that thing knew what was going to happen before it actually happened.

                There are always little glitches and jumps in the film payout, no matter how carefully you splice film or thread the rollers. It could be a momentary stall followed by a quick speed up or, on startup, the film goes from zero to sixty in less than a second but the platter always pays out evenly.

                Yes, they were complicated but, once installed and calibrated, there was near-zero maintenance on them besides keeping them clean.

                If you just clean them every day and give them regular inspections, the Kinoton platter "just works."

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                • #23
                  Actually guys, for platters with takeup elevators (aka "yo yos"), when you finish threading, you actually want to spin the takeup deck BACKWARDS until the motor starts to fight you, meaning in the case of a SPECO you just start to enter the section of the rod that is twisted. This way as soon as the projector is started and is ramping up to speed, within a few frames of movement the takeup platter starts spinning WHILE the projector isn't at full speed yet.

                  This is important because you only have (on most projectors without inverters) maybe 2-3 seconds before the projector is at full speed, so you need to take advantage of that when getting the takeup platter moving. If you spin the takeup forward so the elevator is at the top of its travel, the first couple of feet of film movement don't even begin to start the takeup motor spinning, and as such the projector is feeding at a full 24FPS by the point the takeup platter starts to get any power to start spinning. Not sure how well I worded that, but does that make sense?

                  Also by having the takeup elevator as low as possible, that helps give the feed platter a boost. For example on a SPECO LP-270 if you set the takeup elevator as low as possible (meaning the start of the takeup motor) and OVERSPIN the feed platter by 1/2 of a turn, once the half wrap of film catches up to the 0% mark on the payout arm, most of the payout arm is looking at the takeup variac for it's running speed (it's roughly 10% to 90%). So since the takeup elevator drops past it's normal starting speed and then runs faster to "catch up" before stabilizing, that puts the duration that the payout arm is swinging from 10% to 90% with the takeup elevator in its lowest position, meaning it helps get that feed platter spinning faster so you don't wrap and scratch the first few wraps of film. Again, not sure how clear my wording is, but once you go past 90% of the payout arm speed that's actually just "full power" to the feed motor. Except for the initial start, that's why those LP-270 platters would bounce between 0% and 50% for the majority of the movie. All it was doing was running at the speed of the takeup, then turning off, then running at the speed of the takeup, then turning off, etc. It never needed the "full power" end of the payout arm because the outer diameter of film on the takeup platter was always slightly larger than the payout, meaning if you were to spin the two at the exact same speed, the payout would slowly overfeed. That effect is easily seen if you select BOTH platters as takeup platters.

                  Strong platters were garbage though. Nothing you did would get them up to speed fast enough. Film abrasion ALWAYS happened at whatever was first on the roll, so "running starts" were mandatory with those things.

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                  • #24
                    You're right about SPECOs. I guess I was speaking telegraphically when I said to put the elevator "near the top."

                    If your Variac is set right and your rods are clean, the elevator should naturally come to rest at the right point if you run the projector motor for a few seconds after threading then shut it off. You'll need extra leader to do it that way but I think leader is chattel if you want to have a good presentation.

                    I never remember having any problems with the Strong platters. No, they were not the best platters, by any means, but they were good and serviceable. Since most of their parts were available at local hardware stores, fixing them was cheap and easy. People used to tell me, "Strong platters always scratch film," but my stock answer was, "Only if you're an idiot who doesn't know how to run a projector the right way."

                    Again, with Strong, it was the same as SPECO. Use a long leader and run the motor after threading then let everything coast down to a natural resting point. If the system is in balance when you start the show, startup should be trouble free.

                    I also used the TA-10 automation that needed to have a cue to start the automation sequence after the start button was pressed. By the time the cue passed, the projector would already be up to speed and the platters would be running at speed. If the platter made any scratches, they would be in the leader. Still, I never really saw any scratching beyond what I thought was normal wear and tear. Consider that the same section of leader would be exposed to wear on every startup so, if there was damage, it would accumulate over time. I never saw any scratching that concerned me.

                    When I said to teach your people how to do things right, this is what I meant. I thought this was all mostly understood but I can see how I was assuming that everybody just knew what I was thinking.

                    Regardless of which platters you have, Strong or top of the line Kinoton, you still need to pay attention. It's not about how expensive your equipment is. It is about doing your best to observe what is happening, two feet in front of your face and thinking about what you see.

                    Brad has his way of doing things, I have my way and the next guy will have his own way. There are likely to be things in common and there should also be some established best practices.

                    There really is no "One True Way" to do everything except to say that paying attention and thinking about problems and solving them is a must.

                    Y'know... I think there's a word for that but it's been so long since I heard anybody use it that it's hard to remember. I'm not sure but I think the word I'm looking for is "Professionalism." Is that right? I dunno'...

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                    • #25
                      Brad: couldn't the issue with Strong platters be solved with larger center rings? I never really worked with these, so I don't know, but that would reduce the speed required at show start.

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                      • #26
                        I think it was just that the motors couldn't generate enough torque to handle the weight involved. Larger rings wouldn't solve the problem (and would take away the ability to put two features on the same platter). There always seemed to be a trade-off involving the tension between the motor and the edge of the platter. I know that I spent far more hours than I care to think about tightening and loosening the bolts to move the motors and rarely managed to make the timing perfect.

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