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Dalsa/Codex Workflow

Curtis Clark, ASC, had been planning to make a 30-second spec commercial for Michelob anyway, so when he realized circumstances were converging to make it possible to get his hands on a Dalsa Origin camera and a new Codex 4K/2K Digital Media Recording System, from London''s Codex Digital, he decided he might as well turn his little project into a big experiment. Thus, Clark, chairman of the ASC technology committee, became the first cinematographer to record raw Dalsa 4K images directly to the Codex hard drive system since it debuted at NAB this year in a real-world production environment.

“There were a lot of firsts involved, actually,” Clark says. “I incorporated motion control, which was the first time Origin had ever been used in a motion-control context or with the Codex field recorder. It was also the first time that the Origin was used to shoot 36 actual frames per second, non-interpolated. All this stuff made it a very challenging project, and also gave us an idea what the possibilities might be in terms of putting these different technologies together for the first time.”

Clark used Codex units as A and B recorders, set at 24fps and 36fps, respectively. During production, he says he used the system for video assist, immediate show review, and to output AVI files to a networked laptop running Adobe After Effects in order to test composites of certain motion-control elements. He also used the new Codex “virtual file system” to network uncompressed DPX files directly with Dalsa''s Visualize software, which permitted him to check exposure and color on set using single still-frame references viewed on a calibrated reference monitor. At press time, 4K files from his shoot, rendered as RBG 4:4:4 16-bit TIFF files, were being color-timed at Post Logic.

Conceptually, Clark points out that the basic notion behind the Codex recorder is similar to the methodology that filmmaker David Fincher and others are using these days to record imagery from Grass Valley Viper FilmStream cameras to D.MAG digital film magazines, from S.two of Reno, Nevada, in terms of capturing imagery as raw file-based data on a hard drive direct from camera. (See an upcoming issue of DCP for more on Fincher's workflow.) In this case, however, he was capturing 4K data from the Origin—a significant increase in the amount of data captured on set.

“The disc recorder needs to not only capture and store the data, but also give you quick access to rapid playback of that data, and so, you need a quick interface to be able to access random scenes and takes, along with their associated metadata and timecode in order to have an efficient workflow,” Clark says. “This system was quite efficient in that respect. It does a virtual realtime, quick render of the raw image data captured from the Origin, and for the first time in my experience, that gave me the ability to look at an approximate 1K playback of moving images in realtime on a calibrated monitor immediately after I shot the material. That gave me a significant advantage, and it is my understanding that Codex will soon make 2K playback possible on a calibrated reference monitor.”

Clark emphasizes that the spec commercial, of course, is intended for broadcast playback, and therefore, he would not normally need 4K-source imagery for playback, as he might for a major feature film project. However, he adds, this workflow, once some kinks are worked out, still has potential to improve the quality of final broadcast imagery, in certain circumstances.

“In this case, we were able to take raw data and render files to 4K, 16-bit TIF files in 4K resolution, which are the files that Post Logic is handling (in post-production),” he says. “But in the case of Post Logic, they have built a 4K infrastructure to ingest, play back, and color-correct these files at uncompressed native resolution size. Not all facilities can do that, and of course, for broadcast you wouldn''t necessarily need to anyway. After all, 4K can be quite challenging on [a facility''s] infrastructure bandwidth and disc storage capabilities.

“But, in practical terms, we could, if we wanted, capture at 4K, down-convert the files, and do HD 4:4:4 finishing of this material. The ultimate mastering platform in that sense would still be HD because that is more than sufficient for a television commercial and is the highest quality currently available. But if you take a 4K image and down-sample it, you have so much extra image information, and that allows you to create spectacular down-converted HD images, as opposed to originating in HD to begin with. So, there are even advantages in that regard.”

Clark adds that among the issues still to be fine-tuned with the workflow is the issue of efficiently converting the files to Avid-ready OMF dailies files. “I know they are working on ways to avoid that extra file conversion process that can be time-consuming and sometimes impact your ability to maintain original timecode in the EDL,” he says. “But the imagery is pretty amazing, and it offers some pretty interesting creative opportunities.”