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Digital Intermediate: Inner WorkingsHere's the industry guru telling us how DI really works in the film industry today -- and tomorrow
DMN: When you turn this into video, are you just capturing this into motion jpeg?
Wright: No, the telecine takes it from film to a videotape, typically Beta SP. The videotape is given to the Avid editors; you put it in the deck and the Avid digitizes the Betacam footage onto the hard drive, and they use an internal format called OMF. This gives the editor random access which is what makes it nonlinear editing. So there is where you actually edit your movie.
DMN: And you keep your time code numbers.
Wright: Exactly. You have a separate list that refers the video time code back to the film key codes. You have to get back to the film key codes. So when you're done editing your movie, you have the Avid print out the necessary edit lists that tell which pieces of film are used in what order, to assemble the movie just like the videotape was assembled, in order to, in essence, copy the editing you did on the videotape with the film. That process is called conforming. Cutting the negative to match your edit decision list, whether it's the video, or done on paper -- that is conforming.
DMN: Now wouldn't it make more sense to, when you digitize this film into, say, Cineon frames, just to then turn those Cineon frames into smaller-frame-sized digital footage, and then edit that, rather than go to this analog tape and then capture back into an Avid?
Wright: What you're saying is what will happen in the future, and that's called the "scan-once paradigm." Right now, the cinematographer will take a hundred shots. He will select ten of them to be transferred to dailies, they're called "circle takes." So ninety percent of them -- we know they're no good. The prop fell down in the middle of the take, or whatever. So only the circle takes are transferred to video, which is a subset of what was photographed. Then, of the circle takes, only a fraction of those are edited into the final movie.
DMN: So there's editing done even before anything's digitized.
Wright: Yes. The reason is that today, digitizing is slow and expensive, so we only want to digitize exactly the frames we're going to use in the final movie. In the moderately near future, when digitizing is fast and cheap -- high rez digitizing -- then we're going to do exactly what you said. We will have achieved the "scan-once paradigm." The circle takes will be digitized at high rez, then they'll be down-rezzed to video for the editors to play with, and when the editing is done, we'll just pull those same 2K, high-rez scans and conform the movie. But right now you only want to digitize at high rez, the keepers for the finished movie. This scan-once paradigm is one of the future issues here.
DMN: And everybody's hoping that'll come soon. What do you think, say, five years from now?
Wright: It'll be sooner than that. And don't forget, the high-end movies will be able to pay for it sooner. It was already done once for a movie. [He talks about a movie where this technique was used, the name of which is off the record, but it was a well-known high-budget motion picture released this summer]. But if you have a lot of money, you can do it now, OK?
DMN: What are you using to do the scanning?
Wright: The scanner du jour is the Northlight.
DMN: I suppose that's very expensive per hour. But that will become much less expensive as faster ways of doing this are devised, correct?
Wright: Yes. Faster machines. The Northlight is the hot machine at 2.5 seconds per frame.
DMN: And that outputs 2K frames.
Wright: Yes, 2K scans.
DMN: Into what format?
Wright: It can output either Cineon or a DPX files at 2K resolution.
DMN: Those two file formats are very similar, aren't they?
Wright: Yes, they are.
DMN: They are individual frames, each file is one frame.
Wright: Yes, each frame of film is one separate file, like a tiff file or whatever, but it's a Cineon or DPX.
DMN: Is anyone interested in scanning at higher resolution than that, say, at 4K?
Wright: Well, yes. In fact, the Northlight optically scans the film at 6K, and then internally down-rezzes it to whatever resolution you want.
DMN: So it could do 6K if you wanted. But you might not want to deal with frames that are that big, though.
Wright: You absolutely do not want to deal with frames that are that big. This is one of the other future things, the 4K digital intermediate.
DMN: But right now, it's not possible because?
Wright: It's totally possible, it's just not practical. The film recorders, the scanners, will do 4K. Software color correction systems will do 4K. The hardware color correctors are stuck at 2K. So if you want to pay for 4K scanning, and 4K film-outs, and you've got the time to use a software color corrector, you can DI your movie at 4K today. But it'll cost you a fortune.
DMN: So I would translate that into no one's doing that yet, or very few.
Wright: Very few. Spider-man 2 was done that way. Spider-man 2 was an honest 4K DI.
DMN: Do you think it's worth it to do 4K?
Wright: No. Not today.
DMN: Can anybody really see the difference on the movie screen?
Wright: Yes, if you did a side-by-side, you'd see the difference, but the average movie-goer is perfectly happy with a 2K DI.
Related Keywords:Steve Wright, industry veteran, digital effects, feature films, broadcast television commercials, feature film digital intermediate, contribute articles, DMN, Charlie White