8 bit to 10 bit

Throughout the Digital Intermediate pipeline I have talked primarily in terms of work flow using the highest resolution available. Mainly 16/35mm film scanned at 2K/4K and at minimum, 10 bit and I have suggested log material. Obviously we now have to add HD to the equation as it is a much cheaper option and a good alternative if shot correctly. The truth remains though, that sometimes you will find yourself working with material which has originated from much lower resolution sources and bit depths, such as DigiBeta. Your material these days could equally come from a mobile phone or even originate from a YouTube clip. The point is you simply have no idea what you are going to have to ‘beautify’ or make look good?

A quick note about DigiBeta, an urban myth I have heard many times is that material originating from DigiBeta is 8 bit. I am not sure where this has ultimately come from but I would assume from BetaCam SP, the format before DigiBeta, which was an 8 bit format. The point is though some materials you have to use may only originate from BetaSP, or a much lower resolution source, as that will be the only material available. You will need to adjust your workflow to accommodate; especially coming from field based material and possibly treat it more like an FX piece. Do not despair as this material if treated with care can look pretty good.

 

Digital Film 8 bit ‘vs’ 10 bit

Pioneering commercial turn key solutions became available in the early 1990’s with Kodak’s Cineon and Quantel’s Domino. Both were full end to end off the shelf systems consisting of a film scanner, an image workstation, and a film recorder, today’s standard workflow of the Digital Intermediate. The reason I mention these two specifically, is that I have worked for both Kodak and Quantel and I was interested in the arguments that raged between the two systems. I also happen to be best friends of the lead programmer for Domino, so have a personal interest.

I would say that history would argue 10 bit won but Domino’s system and toolset was exemplary in its construct and the material it output – proof was testament at how quick the system worked and the turnaround of its FX shots, all in, gasp, 8 bit. Although Kodak discontinued the Cineon line in 1997, the technology remains the foundation for many digital image processing systems in the motion picture industry today. Especially the Cineon file format and the concepts behind it are still used in DI.

 

In practice working with low resolution material is not as painful as it sounds. You have to treat it slightly different and respect that ultimately you are never going to introduce information that is no longer there. There are cheats though, like using the interlacing as your friend if the material comes from video or tape.

The material below is from a film called L'amore di Màrja, it forms part of the opening sequence. It is made up from a combination of material taken from the Isle of Wight festival shot in 8mm in the 60s transferred to Beta SP, which was the only material available. The new material to be treated and matched was shot on 16mm and grain and scratches are added, using a combination of varying grain I had on a DigiBeta and a piece of clean 35mm film I got our telecine operator to drag around the facility all day to add dirt and create genuine scratches, he was genuinely enthusiastic about the project. On the transfer we did not use sticky rollers to remove the dust and dirt we left it in the scan, which was combined and composited across the material.

Surprisingly the director made me add even more scratches, which were added using a digital plug in across the entire sequence, including the BetaSP material to bring conformity across the shot. He felt it needed to be obvious and he also made me back off the grade and softness on the 16mm to look cleaner. The client is the boss.

So for one sequence I utilised the following materials:

  • Beta SP - 8mm telecine transfer (8 bit linear YUV)
  • DigiBeta - telecinied grain (10 bit linear YUV)
  • 16mm (10 bit log)
  • 35mm (10 bit log)
  • Plug In - scratch emulator


Notice the colour difference between the two sequences and also that I have softened the image on the graded version to further match the 8mm Beta SP material.
The director actually made me reduce the softness because he wanted to see the main characters faces more clearly.

 

The 8mm Beta SP material was also treated with added grain, scratches and aditional dirt plus digitally enhance scratches using a plugin
across over the entire piece to marry the sequences together.

 

This is the final sequence, courtesy of youTube