We started by watching films from the various periods, either with Marty or at his urging. YCM [Laboratories in Los Angeles] was extremely helpful in providing screening facilities for rarely seen footage and nitrate prints. The two-color Technicolor films we saw were Toll of the Sea, The Black Pirate and an astounding short called Follow Through. We also screened a three-strip Technicolor short called La Cucaracha. We screened a large quantity of small selections of film; often they’d run something for a minute or two, whatever they felt was necessary, and then move on to another. We also tried to talk to cameramen who had worked with those color processes.
Before settling on creating the look digitally, we tested it optically. We pulled four sequences from Gangs of New York [AC Jan. ’03] and handed them over to YCM, who optically created a two-color and a three-strip look with them. The resultant color tones were not quite as enhanced as Marty would have liked, and there was a tremendous level of grain that we were uncertain how to get around. Because this is also a heavy visual-effects project, [accomplishing the looks through] a DI made more sense. And the three-strip LUT gave us an almost exact approximation of the Technicolor ‘look.’ It wasn’t quite as glorious as an original print, but it was a very vivid rendering.
Legato: After going through all of Marty’s visual research, it occurred to us that perhaps the filtration of the three-strip taking camera created the color palette that we know as Technicolor that it wasn’t necessarily the dye-imbibition process applied to the print. That’s when we thought of taking a photo and using Adobe AfterEffects to digitally create a red filter, green filter and blue filter. This approach filters out the other colors from each one of those layers, just like the filters in the old three-strip taking cameras did, and then what you’re left with is a digital form of that Technicolor look.
Using this as a reference, Josh Pines at TDI made a table that would sufficiently characterize the color space of the film. The layman’s explanation is: picture a series of chip charts showing all the different colors of the spectrum, hundreds of thousands of colors. I took that and put it through the same process by which I’d balanced the scenes that we shot into a Technicolor look. Picture a thousand steps of blue; if, within those thousand steps that your eye accepts as blue, you had some component of red or green, the filter would remove the red and green from some of those steps. So instead of having a thousand steps of blue, you’d have a hundred. It’s essentially a conversion chart, like from feet to meters; it would recharacterize every pixel to create a palette with a much-reduced and compressed color fidelity, identical to the digital process I used to mimic the three-strip Technicolor process. This is what was built into the LUT, which we subsequently slipped into the projector in the DI suite and color-corrected through.
Why did you need a LUT to do this? Couldn’t you just time the scenes this way in the normal DI process?
Legato: In trying to digitally re-create Technicolor, every shot in the film becomes an effect. And if you were to render it that way and crunch it on all these machines, it might take an hour just to do one scene because of all the manipulations it has to go through. With the LUT, because the instructions are built into a graphics-processing card, it only takes about four seconds per frame. It happens much closer to real time. The easiest way to understand the difference is this: if you go to your TV and change the hue control, it happens in real time because it’s just twisting the signal around through the hardware. The LUT, which is hardware, allows you to do that [on a more elaborate scale]. These very powerful graphics cards are able to process it on the fly.
Richardson: It was extremely vital for us to work in real time. Otherwise I’d get very nervous about what would happen when I got into the digital suite. Am I going to sit there and correct this as a normal film, send it out, and then have it come back looking somewhat like Technicolor, which I’d then have to correct all over again? No matter what happened, I knew I’d have to make adjustments. So how do I do it in real time? That was the concern, and the LUT was the solution.
Legato: When Roger Deakins [ASC, BSC] timed O Brother, Where Art Thou? he created a very specialized look. This is a step beyond that. It’s like making a digital filter that you can apply in the projector and color-correct through, in real time, to make any look you want. Much like we made these Technicolor looks, a cinematographer could say, ‘I want all of my day-for-night dailies to look a certain way,’ then create a LUT for it, and then apply it to every shot. Once the correction is finished, the Cineon files get ‘baked in’ with the information from that LUT: it turns from hardware into software that digitally reproduces the look so it can be filmed out. It’s a very consistent way of creating a sophisticated look that would otherwise have to be done on a shot-by-shot basis.
How many LUTs were created for The Aviator?
Legato: Josh created two Technicolor looks, two-color and three-strip, but within each of those looks there were several LUTs. That’s because back when filmmakers shot in Technicolor, they had only one version of the blue filter in the taking camera. Circumstances would, of course, change on a scene-by-scene basis for example, if you had a lot of sky in the frame, you might want less of a blue filter but they didn’t change the filters in the camera, they simply adjusted the dyes at the printing stage. We had to do a similar thing, except with a modified LUT. If a scene had too much blue in it, it might get noisy in those areas. So we’d slide LUT #2, which had 70-percent blue instead of 100-percent blue, into the projector and color-correct through that to see if we liked it.