Secondary Grades are Nothing New

Last week I posted an article I wrote a while back (originally for RedShark News), entitled “Why You Can’t Relight Footage in Post”. You may detect that this article comes from a slightly anti-colourist place. I have been, for most of my career, afraid of grading – afraid of colourists ruining my images, indignant that my amazing material should even need grading. Arrogance? Ego? Delusion? Perhaps, but I suspect all DPs have felt this way from time to time.

I think I have finally started to let go of this fear and to understand the symbiotic relationship betwixt DP and colourist. As I mentioned a couple of weeks ago, one of the things I’ve been doing to keep myself occupied during the Covid-19 lockdown is learning to grade. This is so that I can grade the dramatic scenes in my upcoming lighting course, but also an attempt to understand a colourist’s job better. The course I’m taking is this one by Matthew Falconer on Udemy. At 31 hours, it takes some serious commitment to complete, commitment I fear I lack. But I’ve got through enough to have learnt the ins and outs of Davinci Resolve, where to start when correcting an image, the techniques of primary and secondary grades, and how to use the scopes and waveforms. I would certainly recommend the course if you want to learn the craft.

As I worked my way through grading the supplied demo footage, I was struck by two similarities. Firstly, as I tracked an actor’s face and brightened it up, I felt like I was in the darkroom dodging a print. (Dodging involves blocking some of the light reaching a certain part of the image when making an enlargement from a film negative, resulting in a brighter patch.) Subtly lifting the brightness and contrast of your subject’s face can really help draw the viewer’s eye to the right part of the image, but digital colourists were hardly the first people to recognise this. Photographers have been dodging – and the opposite, burning – prints pretty much since the invention of the negative process almost 200 years ago.

The second similarity struck me when I was drawing a power curve around an actor’s shirt in order to adjust its colour separately from the rest of the image. I was reminded of this image from Painting with Light, John Alton’s seminal 1949 work on cinematography…


The chin scrim is a U-shaped scrim… used to cut the light off hot white collars worn with black dinner jackets.

It’s hard for a modern cinematographer to imagine blocking static enough for such a scrim to be useful, or indeed a schedule generous enough to permit the setting-up of such an esoteric tool. But this was how you did a power window in 1949: in camera.

Sometimes I’ve thought that modern grading, particularly secondaries (which target only specific areas of the image) are unnecessary; after all, we got through a century of cinema just fine without them. But in a world where DPs don’t have the time to set up chin scrims, and can’t possibly expect a spark to follow an actor around with one, adding one in post is a great solution. Our cameras might have more dynamic range than 1940s film stock, meaning that that white collar probably won’t blow out, but we certainly don’t want it distracting the eye in the final grade.

Like I said in my previous post, what digital grading does so well are adjustments of emphasis. This is not to belittle the process at all. Those adjustments of emphasis make a huge difference. And while the laws of physics mean that a scene can’t feasibly be relit in post, they also mean that a chin scrim can’t feasibly follow an actor around a set, and you can’t realistically brighten an actor’s face with a follow spot.

What I’m trying to say is, do what’s possible on set, and do what’s impossible in post. This is how lighting and grading work in harmony.

Secondary Grades are Nothing New