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  • Odd film wear pattern

    Can anyone identify the cause of this film damage? For some reason uploading MOV video files is not permitted here so I couldn't include the video I took to show it at multiple lighting angles, but the pattern consists of columns of dots with some vertical lines or smearing between them, and it occurs across the entire frame. I've seen the exact same pattern before, but it was usually on shredded studio prints that had all kinds of other damage. This time it was a brand new print, and I was only the third projectionist to run it. Apparently this happened during a single screening, and it's persistent through all reels.

    It's on the base. My first guess was that it may be caused by a soundhead pinch roller (Simplex / RCA style, making contact with the picture area) but I would have expected that to be on the emulsion side.
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  • #2
    Actually I've Seen this on other Brand new prints (from a lab in California...) as well, even before the prints have run through any projector. My guess was that it must have originated somewhere in printing, or probably more in developing.
    ​​​​​

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    • #3
      Sascha, the dots you saw on other Fotokem prints on the base side was from their demand drive style processor. Instead of using sprockets to drive the film like a projector, they use rollers that have rubber tyres on them. The tyres have little bumps to grab the film and if their concentrated wetting agent (think "Photoflo") isn't mixed with the exact portion of water, those "drying spots" will occur. We can remove the spots through our rewash processor though.

      What Jesse is showing is something a bit different though. That's not tyre marks though. Perhaps Jesse can upload it to youtube or use Handbrake to convert it to an H264 mp4.

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      • #4
        Originally posted by Brad Miller View Post
        Sascha, the dots you saw on other Fotokem prints on the base side was from their demand drive style processor. Instead of using sprockets to drive the film like a projector, they use rollers that have rubber tyres on them. The tyres have little bumps to grab the film and if their concentrated wetting agent (think "Photoflo") isn't mixed with the exact portion of water, those "drying spots" will occur. We can remove the spots through our rewash processor though.

        What Jesse is showing is something a bit different though. That's not tyre marks though. Perhaps Jesse can upload it to youtube or use Handbrake to convert it to an H264 mp4.
        Hi Brad,
        Thanks for the explanation! I remember those marks were visible on both OUATIH and ALL QUIET ON THE WESTERN FRONT. Afair they weren't visible on screen thought.

        Interesting topic, I am also curious what could create those marks shown by Jesse.

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        • #5
          I agree with Brad. It looks like water marks, either from poor rinsing or some kind of contamination on the film after it was processed. I can't tell where the water marks originated but Brad's explanation makes sense.

          In any case, the solution would be to re-wash the film and dry it properly.

          If you can treat the print with Film-Guard, it might help but you'll have to consider that option carefully. Film-Guard might not remove all the marks but, more importantly, you'll need to think about treating somebody else's film with Film-Guard which will remain on the film after it leaves your hands.

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          • #6
            Looks like mold or fungus to me. When I was collecting film, I had reels and entire prints with that mottle on it. Definately is if there is a lot of footage with that on it.

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            • #7
              I too think they are water spots from less-than-perfect lab work. Last month I had a
              brand new film-out print of a recent release from a lab on the East Coast, with those exact
              same marks on the base side of the print. - - in fact, I've had several prints from that same
              lab with the same marks on the base side but the last one was the worst. Fortunately in
              most scenes, they didn't show up on screen, unless you were really looking for them.

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              • #8
                I grabbed a couple of different sizes tyres from our lab parts inventory. They are designed to mount on flat surface rollers, not the curved "Kelmar-type" in the picture here, but I included the Kelmar-type roller as a size reference since this one was sitting nearby.

                Jesse - can you upload the video to youtube or somewhere? I'm curious to see this from different angles to try and determine what it is.
                Attached Files

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                • #9
                  To me it also looks like calcium or other mineral residue from non-distilled water droplets. Just curious if you can wipe them off of a small section of affected film with a damp microfiber cloth without any real efforts.

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                  • #10
                    I've attached a video and a different still.

                    I can definitely see it being caused by the tires that Brad pictured. The dots are in columns, with the alternating rows vertically offset from one another exactly like the bumps on the tires.

                    It's the only print they struck so I treated it like it was archival. Kept the handling to a minimum and did not attempt to clean it. Next time I get a shredded studio print with this pattern I'll see if it can be cleaned off. From what I could see the marks were not visible on screen, but I was running reel-to-reel for a single screening without a test run, so the amount that I was actually watching was limited. I was intentionally watching during light scenes to see if the shouldered roller scratching was visible on screen, and didn't see that either. If the dot pattern was visible to any significant degree, I probably would have seen it in those shots.

                    Mark, It's definitely NOT mold.
                    Attached Files

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                    • #11
                      Jesse- Now that I've seen your video, that's exactly the same type of marks I saw on the print
                      I mentioned in my post. I worked in a film lab for a while years ago, so I recognized them as
                      an artifact of poor lab-work. Like you, I only had a chance to run the print once for a special
                      preview, and then immediately ship it out to another theater overnight for a show in the mid
                      west. But I remember writing them a note about the spots on the print when I shipped it.
                      But, as we've both observed, in most scenes they weren't noticeable on screen . I might have
                      taken some pictures too- - I'll see if I can find them.

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                      • #12
                        I'm not going to claim that I perfectly understand all the steps in this labs film development process, but having developed some film myself (pretty long ago), I don't really understand why you want to transport newly developed, wet film with those rollers instead of via the sprocket holes. Maybe someone can explain the reasoning behind this?

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                        • #13
                          I'm curious too - Maybe the emulsion side is still a bit fragile and it's actually gentler to use those rollers than to focus everything on the edges?

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                          • #14
                            Just out of curiosity, what title and stock/edgecode/year of print production (i'm assuming 2023 or 24)? Who knows, I might end up with this one some day too.

                            My hunch would be lab related too. A look under a good loop or scope might prove the chemical vs damage thought. The idea that it first appeared after a screening seems a bit erroneous, probably just didn't get inspected that closely at the preceding ones?

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                            • #15
                              Now that I've seen the video, I feel pretty certain that the problem is caused by drag-out: When the film goes through any processing step, some of the liquid is carried on the surface of the film to the next component of the system.

                              When the film goes through the developing solution some of it gets dragged out and ends up contaminating the next bath. (The stop bath?) The stop bath gets dragged out to the fixer, the fixer gets dragged out to the fix neutralizer and so on. (Whatever the processing steps for this particular type of film are.) There should be plenty of rinses and blow-off devices between steps but it's impossible to completely stop drag-out. There's bound to be something left on the film as it goes through each step of workflow.

                              The solution is to meticulously clean the entire machine, rollers and all, frequently, after so many feet of film are run through.

                              So, yes, I agree with Brad that something got on the fingered, rubber rollers, contaminated the film and left those marks behind when the film was dried but I don't, necessarily, agree that it was simply that somebody mixed the PhotoFlo wrong. It's actually pretty hard to mix the stuff wrong. The mix ratio that I use is 200:1 but I've seen people mix it at different ratios without causing trouble and, unless, it was mixed at a really, really wrong ratio, it still doesn't leave marks on the film. It could be but I still think drag-out is a more likely cause.

                              I think it's more likely that some slack-ass operator didn't clean the machine and change all the processing baths when he should have. It's easy to imagine that somebody would have tried to squeeze a few more reels of film through the machine, before cleaning it and replenishing the chemistry in order to save some time or shave a few pennies from the budget. Maybe management is even ordering operators to clean less frequently as a budget saving measure.

                              Regardless of the reason, my vote is "Drag-out."

                              I'm not completely certain but it's my guess that they use those fingered, rubber rollers to reduce the potential for damage on the film. If you use sprockets at every turn, you're going to concentrate a lot of stress at the edges of the sprocket holes. As fast as I've seen some film processing machines run, one small hiccup could cause the sprockets to tear the film or the machine could get damaged. Using rubber rollers might serve to distribute stress over a wider area and reduce potential for damage because if there comes a hitch in the film path, the rubber rollers will slip and only a small portion of the film might get scratched or abraded instead of messing up a whole batch of film.

                              Yes, rubber rollers can leave marks and scratches on film, especially when it's wet. If they are cleaned frequently, the chances are small... But...If somebody doesn't clean the machine when they are supposed to, it will leave marks on the film...as we have seen!

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