From One-Light To Final Grade:
Colourist Terms and Workflows
by Kevin Shaw

This article discusses some of the different terms and workflows used by colorists. The terminology varies, and the techniques evolve but the concepts remain the same.

Introduction

Color grading has always been an essential part of using film for video. Consequently the tools have become increasingly sophisticated, and expectations have risen. Now these same tools are being applied to film finished projects, where they are not essential, but they are expected. Color grading has huge production value. Yet with all the new tools and features, session times have remained much the same. Colorists have therefore had to discover better, more efficient workflows.

To begin at the beginning, there is no such thing as a one light. Of course I could set a single grade and let the film run, but most clients would reject it. If a one light transfer really worked, there would be fewer colorists, and color correctors would be less sophisticated. Usually the people that believe in one-lights also believe that it takes 60 minutes to transfer an hour of film, even if it’s on 6 rolls, without cores and tails out.

The problem is dynamic range. The dynamic range of original camera negative (OCN) is simply too great to capture as high quality video with a single setting. It is also the reason that the auto correct buttons on telecines disappeared decades ago.

There are good reasons to do one-light transfers, but creating any sort of a master copy is not one of them. One-lights provide useful exposure information for the cinematographer, and can be used instead of a rush print. A rush print is a balanced film print, with a print out of the red, green, and blue printer light values used. A one-light telecine grade has no print out, but still shows differences in exposure. There have been attempts to mimic the RGB print out in telecine, but none have been commercially successful. A test chart shot specifically to set-up the one-light grade makes this type of evaluation more effective. Suitable charts vary from a simple Kodak card with black, 18% gray and white strips, or GretagMacbeth color patches, to more engineered products such as those supplied by Gamma & Density. Other than the rush print, the one light is the only way of checking exposure that has stood the test of time.

Ideally, when the final grade is not going to be from the original negative, there should be no colorist intervention at the initial transfer stage, and the tape or disk based copy should be an accurate digital copy of the negative. However, because of the dynamic range issues, this workflow generally uses a technical grade or a calibrated scan.

If the reason for requesting a one-light transfer is cost based, a colorist can gently ride the controls during the recording. If the material is consistent to start with, this produces a reasonable copy for offline editors. A best light is preferable for multiple location shoots, available light shots, cut negative jobs and finished programs.

Often the Director of Photography (DP) will prefer to do a best light to achieve the intended look early in post-production. This ensures that even early viewing copies look “correct”.

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