HISTORY & DEVELOPMENT OF DIGITAL INTERMEDIATE
The year 2019 marks the twentieth anniversary of the production of O Brother, Where Art Thou?, a movie considered by many to be the first Digital Intermediate. Digital Intermediate is now the standard process for the finishing of feature films. The concept grew from the practice of scanning visual effects plates, doing digital compositing and then recording the finished composite back out to film negative so it could be cut back into the negative. It was therefore the “digital intermediate” process, with film still being used for origination, distribution and exhibition. Scanning and recording were expensive and the process took a long time. Despite this, innovators saw that entire movies could be color graded and finished digitally and then recorded back out to film. But it wouldn’t be easy.
In Los Angeles, Cinesite, a Kodak subsidiary, put together the team and technology that would be responsible for the scanning, color grading, conforming and recording back to film of O Brother, Where Art Thou?, which was completed at the beginning of 2000. Prior to O Brother, a low budget independent feature had been completed already – Urbania, shot on Super 16mm and finished in the summer of 1999 had provided an opportunity to test some of the technology and processes. O Brother was directed by the Coen Brothers and the cinematographer was Roger Deakins ASC BSC. If you could look at the original footage, which the filmmakers never want to be seen, the foliage is lush and green because it was shot in June and July in Mississippi. The filmmakers, however, wanted the movie to feel like it was dry, dusty and brown and almost like a picture book set in the Dust Bowl. They had experimented with photochemical processes but realized that they wouldn’t be able to get the look they wanted. Traditional film laboratory color timing is restricted to the balance between the three primary colors and so one aspect that would be impossible to achieve at a lab is the hue adjustment required to change the color of the foliage from green to brown. Roger Deakins had heard that Cinesite was experimenting in this area and so he approached them during pre-production. Interestingly, the Coen Brothers didn’t even use Avid to cut their film but they agreed to try a cutting edge technique to color grade O Brother Where Art Thou?
The project was completed at Cinesite by senior colorist Julius Friede and his team, who overcame obstacles like the lack of a calibrated digital projection solution or a digital conforming tool. Once the filmmakers knew they would be color grading the film digitally, they adjusted how it was shot. For example, the original colors are more saturated because Roger Deakins knew this would give him more flexibility to adjust in the grade. No filters were used because that could restrict the flexibility of the grade. The process was labor-intensive – in the day, Julius would grade with Roger Deakins with the conformed negative loaded on a Spirit Datacine. They used a monitor calibrated to mimic print film because digital projection was still in its infancy. After the supervised grading session the negative would be transferred to disk with the color decisions applied. Each shot was transferred with handles so that digital opticals could be added.
Every night, certain shots were recorded to film and processed at Deluxe so Julius Friede and Roger Deakins could see what they looked like on film. A calibrated digital projector would have alleviated the need for nightly film outs. Once they viewed the film out, they went back to the grading suite and made adjustments based on what they saw. Another additional step was required because of the lack of disk-based conforming tool. The opticals – mostly dissolves and fades to black – were created and rendered using Kodak’s Cineon software. The shots were then filmed out on a Kodak laser film recorder sequentially to create conformed digital negative reels from which the print is made. Anyone involved in the project will testify that it was painful at times but the finished movie looks stunning, particularly once you’re aware of how bleeding edge the process was.
In Europe, Éclair lab, a film laboratory in Paris was also experimenting – 2001 would see the release of Amelie, shot by Bruno Delbonnel ASC AFC, which was also digitally graded and recorded back out to film, giving it an other-worldly look with certain colors isolated and accentuated that again could not have been achieved in a film laboratory.
One question that often comes up in post-production for HDR is whether the HDR or SDR version should be graded first. Ideally, the HDR should be the master grade, and then the SDR should be a trim pass. Knowing your distribution channel is critical. If we use Netflix as an example, they require a Dolby Vision™ VDM (video display master). Mastering for Dolby Vision™ requires a color grading tool that is Dolby Vision compatible (Filmlight’s Baselight, BMD’s DaVinci Resolve are two examples) and an HDR reference grade mastering monitor that meets the Dolby Vision minimum specifications. The delivery to Netflix is a single-source IMF master which contains the HDR master, along with the “trim pass” metadata to derive SDR streams. When you stream a Netflix show to your home, Dolby Vision-certified TVs handshake with the streaming service and deliver the best-looking image possible, based on the capabilities of that specific TV model.
Over the next few years, some key technologies began to be more widely available – digital projectors, software-based color grading tools like Filmlight’s Baselight and 3D look-up tables that more closely matched projected print film are a few examples. And of course theatrical distribution was quickly switching to digital projectors. These trends, along with the vastly expanded creative palette provided by digital color grading, the increase in processing power and the decrease in the price of storage, plus the huge expansion of the number of visual effects in movies, meant that Digital Intermediate would quickly become the norm for feature film post production. And just like on O Brother, Where Art Thou?, color design often begins in pre-production. The color decisions made in pre-production and on-set by the creative team need to be carried through to visual effects and post production – companies like PIX and CODEX make this process seamless.