Announcement

Collapse
No announcement yet.

Library of Congress Prints

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    Originally posted by Ryan Gallagher View Post
    Having said all that, I may personally pick up one FT 35mm reel to use as a baseline to compare how much our house reels are contributing to tracking problems.
    That and/or bring in my NIB sheet metal style goldberg reels for comparison.
    Remember my warning. Most reels from Goldberg, even as recent as 2024 built reels, are NOT in-round. So just because they are new really makes no difference. The question is are the hubs perfectly round, and are they actually perfectly centered? If not, they will contribute to cinch scratches at the end of the reel and cause instability in SRD tracking.

    This link is of is a video showing how those mass-produced 4 inch cores used in clip-together reels aren't even centered. What happens is every single revolution you have looser and then tighter backtension as film is pulling off of it.
    www.film-tech.com/ubbpics/off-center-cores.mp4

    Comment


    • #32
      Originally posted by Ryan Gallagher View Post

      I have AFG-1 in route that might prove useful in the alignment space for mounting and dismounting our DTS readers in the future. Ideally I'd love to get our quick release plates back in working order, that or a custom mount for the 70mm DTS in a way that can utilized without making the stack taller.
      What is an AFG-1?

      Pics below are of how I handle the different penthouses.

      Picture 1 shows the 35mm path utilizing all digital formats.

      Picture 2 (with the lights off) is the 70mm film path which simply follows a diagonal path entering (or bypassing) the DTS70 reader and directly into the mag penthouse.

      Picture 3 shows the feed reel mounted on the back of the console. To swap formats the shafts and rollers just pull out like a Kelmar rewind table for swapping. The recessed rectangle on the back of the lamphouse is where a film cleaner mounts.
      Attached Files

      Comment


      • #33
        Originally posted by Brad Miller View Post
        But if you run your "house" reel of film, I'll bet you don't see those blips on the waveform, do you? When acetate film shrinks, depending on how it was wound and stored will often cause a tiny, tiny, tiny bit more shrinkage on one side (or point) of the stored reel...which is likely what you are seeing on the scope.
        Noted. And no we probably won't, though in run up to this we did not inspect the waveform that closely, just noted that at least one reel/reader combo was exhibiting higher than normal block errors.

        Below are pictures of how I typically setup rollers for the running of loops. If done properly, these rollers can live there permanently like this and not interfere with running of reels. (Ideally I would have used a longer bolt on top of the SRD penthouse, but again since there is effectively zero tension there when running a loop, a short twist like that isn't hurting anything.) The reason for this is you don't want to start scuffing up the SRD track...or in the case of these pictures, you don't want to scratch up your target loop. Plus this design keeps the film from dangling in front of the lens when you are making critical adjustments.
        Yes revisiting my loops to check SRD error rates would be good too, removes the arm/reel from the equation. We have several, and I made some new ones recently from trailers. Have been looking into a good way to hold them away from the projector and light path, thanks for the example. We might have those kind of roller parts from our platter lying around. Predecessors just put a piece of gaff tape on the top of the mag head corner to reduce the scratching. But loops have a short service life with this approach.

        Remember my warning. Most reels from Goldberg, even as recent as 2024 built reels, are NOT in-round. So just because they are new really makes no difference. The question is are the hubs perfectly round, and are they actually perfectly centered?
        Noted on hub quality and size, even on the rivited "new" goldberg reels.

        Picture 1 shows the 35mm path utilizing all digital formats.
        While I do own a SDDS system myself (that needs some TLC), we are not aiming for anything that custom, although impressive. Really I just want to design a way so both the 35 and 70mm DTS readers can either be swapped easily or remain mounted along with the 702s, and any necessary improved bypass paths. Keeping the DTS readers off the top so step ladders are not needed to hang reels would be a huge plus. All future dreams. Technically we can leave 70mm mounted now, have ceiling clearance and a bypass option, but one of our quick-swap plates is broken, and that whole stepladder business. Only doing 70mm one week a year means we'd rather them just not be there the rest of the year.

        Picture 3 shows the feed reel mounted on the back of the console. To swap formats the shafts and rollers just pull out like a Kelmar rewind table for swapping. The recessed rectangle on the back of the lamphouse is where a film cleaner mounts.
        Does your console mounted feed reel mode even use a clutch? Seems like that path would have enough drag tension that it would barely be needed.

        What is an AFG-1?
        Steel alignment film and AG1 gate alignment tool came up over in this thread. (https://www.film-tech.com/vbb/forum/...5490#post45490. AFG1 is the Lavezzi 35mm steel film part number. It seems a hard to find useful bit of ki these days so I jumped on one from CFS.

        Comment

        Working...
        X