Behind The Scenes, 14 November 2018: A new colour grading system for SWFTA
by James Gibbs, South West Film and Television Archive
The Box has recently purchased a new colour grading system for working with the archive film collections. This compliments the film scanner that was purchased last year. The two pieces of equipment are helping the team prepare a huge selection of films for display in our new galleries.
The film scanner digitises our film collections to an incredibly high quality with a resolution that is greater than most of our films. Each film is saved as a DPX Log file – an amazing uncompressed digital preservation copy of the film as it maintains the resolution and dynamic range of the original. Unfortunately these files are huge – too large to be played by most computers. They are also very lacklustre to watch with a flat and dull appearance.
To show our films off to their full potential, they need to be graded and then exported in a more useable format. Grading is the process of adjusting and manipulating the colours and tonal ranges of film and video.
In a pure film production, the grading is called colour timing as, when the film is printed, it’s exposed to various coloured lights for different lengths of time to shift the colour of the film. The operator is known in the USA as a Colour Timer and in the UK as a Colourist.
These days colour grading is often done digitally. In the case of feature films or television programmes, the grade is usually about achieving a certain ‘look’ to create a mood or feel. It can also be simply about matching different cameras together, so the shots all appear the same in terms of colour and tonality.
In the archive world the grade is usually designed to faithfully reproduce the original film. This is something which is open to personal interpretation and so no two people will produce the same grade……….
It’s also about restoration: as our films age, the colours fade to varying degrees giving an odd look – the most common is a red/magenta colour. During grading we can adjust the colours to help counteract the fading (if only we all had our own personal colour grade!) and restore the digital copy of the film close to how it would have originally looked.
The film clip below is taken from the Westward Television series, Walking Westward (no walking in this shot though), and is a perfect example of colour fade. On the left is the DPX Log file direct from the scanner. In the middle is the conversion from the logarithmic tonal range to linear tonal range. This still shows the colour fade that has left a very red looking colour cast. Finally on the right is the graded and colour restored version. You can see what a difference the colour grading has made.
The grading system has a few different elements to it:
- A powerful computer with incredibly fast data storage, plus a powerful graphics card to do all the hard work.
- A purpose designed keyboard and a grading control panel to make operating the software as quick and straightforward as possible.
- A very high quality video monitor to accurately judge the colour and tone of the film.
- We run two bits of software for colour grading, Davinci Resolve and Premiere Pro. Anyone who goes to the cinema or watches television will have seen films and programs edited and graded using these pieces of software. Sadly for the Colourist, much like lighting and sound for film and television, if the job is done well, all their hard work goes unnoticed as the results will just look right!