October 15, 1997

The lab has been dragging a little on making the corrected print, but it looks as if we'll be able to see it by the end of the week, if Robin's work schedule permits.

Today Tony from Lab-Link wanted to know if I needed pull-ups before he started making the print. Alarmed, I asked him what pull-ups were, and didn't get an answer that I understood completely. He sent me to Fran at Zounds, who said that I didn't need pull-ups, that she had already told Tony that, that I shouldn't worry about it. I asked her to explain what pull-ups were, but I still didn't quite get it. Anyway, I called Tony back and told him that I didn't need pull-ups and to go ahead and make the print. There's always one more thing in post-production to make a newbie feel ignorant.

Anyway, I sat there after I got off the phone and mulled over what Tony and Fran had said until I figured out what pull-ups are. Want to hear about it, even though it has nothing to do with my film? Skip to the next diary entry if you don't. On the path of a film through a projector, the sound heads are located well after the gate, which is where light is shined on the image. The gap is about 25.5 frames for 16mm films. This means that when you are seeing a particular projected image in the gate, you are hearing a part of the film that passed through the gate 25.5 frames ago. Which means in turn that you have to slide the sound track forward 25.5 frames when you put both image and sound on the same strip of film. (A print with both image and sound is called a married print.) If you are looking at the beginning of a married 16mm print, you see 25.5 frames of sound before you see any images, and if you are looking at the end, you see 25.5 frames of image after the sound track has stopped.

None of this makes any difference if you are never going to edit together two reels after they come out of the lab: they are designed so that image and sound will begin and end together on a projector with an appropriate gap between gate and sound heads. And I'm never going to edit my 30-minute reels together, so none of this has any relevance to my situation. But 35mm films come out of the lab on 20-minute reels, and it is common to edit them together before projecting them. And here we see the potential problem. Suppose you cut away everything after the last image on the first reel, and everything before the first image on the second reel, and splice them together. If you look back at the last paragraph, you'll see that you've cut away the first several frames of the sound track on reel two, and left a dead space in the sound track.

The solution is to take the first several frames of reel two's sound track and place them at the end of reel one's sound track, opposite the final frames of the image, when you make the print. These bits of transposed sound track at the end of each reel are called pull-ups.

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