SOME TECHNICAL DETAILS
Evidently, nowadays more and more films are shot on dematerialized digital platforms. This evolution spurs research to find the best possible quality/file size ratio. Currently, the equipment manufacturers (Arri, RED) offer RAW mode storage: direct saving of the data directly from the image sensor. We will skip over more complex technical explanations (but Paul Englebert, the image wizard at DBG will be thrilled to explain everything if you contact him – 02/653.73.23), however it is important to know that when working in RAW format, the calculations are not made by the camera itself, but by a separate workstation. Over the years, the raw definition (number of pixels) has become higher on all cameras. That is a good thing. It makes it possible for video to position itself at roughly the same level as good old film in terms of image quality.
At this time, each image has a large file size and the usual editing programmes such as Avid and Final Cut Pro can no longer handle to put them in sequence. Especially considering one hour of RAW rushes takes around 600Go, both on the Alexa as on RED’s Epic.
Moreover, in order not to lose any information depending on lighting circumstances, the images are « de-emphasized ». Contrast and saturation are intentionally limited. This way, no data risks to be clipped. But if the image isn’t manipulated off-camera, it means it shows up completely washed out.
In short, digital images filmed by a camera (the rushes) cannot be used as such for editing and post-production purposes. An extra « digital development » phase needs to be added. DNA, installed by Dame Blanche Genval, makes this possible.
WHAT DNA ADDS
DNA is a mobile lab which can be rented for a day or for a longer period of time. The station is handled by an operator/colour grader who gives advice about the entire digital operation. It makes it possible to view, control and treat rushes on-set, in a reliable way. In the end, working this way leads to savings during the post-production process whilst optimizing the initial image quality.
There are other undeniable advantages : the rushes won’t be lost or damaged, because the memory cards are transferred onto secured disks with transfer control and copy reports. For the insurance companies, this option means a lot less stress as well. In turn, this can lead to less costly policies for the production.
The mobile DNA lab makes two copies on portable harddisks of the rushes on the camera’s cards. It does this for every day of shooting. The harddisks with daily rushes are named LabRoll. One goes to the production. It is a mirror copy of the rushes used as archives. The production also receives pre-graded QuickTime files for a control viewing. During the shoot, a reference screen and measuring equipment make it possible for the cinematographer to view the rushes in optimal conditions. The settings for the grading on the rushes will return during the final grading after editing. The editor has pre-graded Apple ProRes or DNXhd files.
One time per week, for example, the other LabRoll copy with DPX rushes will be sent to the post-production lab. The grading will then start based on the raw rushes (RAW), or based on pre-graded images as seen during editing.
Evolution ? Revolution ? A bit of both. Soon, DNA might very well be an essential element of their projects for production companies.
