American Cinematographer - January 2012 - 76

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Go with the Flow
codec. The cinematographer on the show may value the difference between shooting 4:2:2 or 4:4:4, but, whether he knows it or not, his footage isn’t being handled properly.” Even when the transcoded material is used only for offline editing and the original full-range camera files are used for the final color grade, workflow hazards might lurk around the corner. I recently experienced one of these on an Old Navy commercial I shot with Red Epic cameras. The Epic’s Mysterium-X sensor has a native aspect ratio sized to the DCI standard of 1.89:1. Filming for a TV commercial, we set the in-camera framing guides for 16x9 (1.78:1), which represents a slight crop of the sides from the full sensor size. Transcodes were performed on set and cropped in RedCineX to our desired aspect ratio. After editing was completed, the original raw .r3d files were conformed at the post house for final color correction. Many contemporary color correctors are able to work directly with the raw .r3d files by utilizing a RedRocket card internally to help process and realtime deBayer the Redcode source material. However, in order to crop the 1.89:1 material to the 1.78:1 aspect ratio, a software checkbox must be selected for either “Fit to Width” or “Fit to Height.” “Fit to Width” uses the entire width of the recorded frame and leaves a slight letterbox on the top and bottom of the frame. “Fit to Height” uses all of the height information and then crops the image at the 1.78:1 aspect ratio of the HD delivery spec. Erroneously, the post housechose “Fit to Width,” but the client found the resultant letterboxing unacceptable. The post team then attempted to remedy the situation by pushing in on the final HD image to fill the height of the 16x9 frame, but this made the footage lose sharpness, which further dismayed the client. At this point, the producer called me to ask why our commercial looked “soft.” After determining where the problem began, we had the post house go back to the original files and lay

This illustrates two sample workflows that are possible when image capture is accomplished with the Arri Alexa.

print? Or do they wish to have the transcodes provide files that can be edited and also used to create the online, much like taking color-corrected dailies back into a telecine for a final tape-totape process? The latter option presents a red flag in terms of the effect it can have on the quality of the image. Mike Most, a senior colorist at post facility Next Element, explains, “For many, the word ‘digital’ is completely misunderstood. It can be nearly impossible to convince some producers that there is a difference between this digital format and that one. “A good example of this can be seen on many productions shooting on Alexa cameras and recording to the ProRes 4:4:4 codec, which is a compressed format to begin with,” continues Most. “As far as producers are concerned, they are shooting on ‘digital,’ so it’s all the same, but the problem is that they will then take that ProRes 4:4:4, convert it to DNxHD 115 — a mid-range Avid codec — and bring it
76 January 2012

into an Avid Media Composer. Then they cut the show and output that as their color-correction master. In the

process, they’re losing a lot of quality because they are subjecting [the footage] to two separate compressions and leaving it in a mid-level data-rate
American Cinematographer

Diagram by Christopher Probst.

“It can be nearly impossible to convince some producers that there is a difference between this digital format and that one.”

American Cinematographer - January 2012

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