Color grading basics
Color correction means making the image right: exposure, balance, contrast and shots that match each other. Grading means giving it an intention: cold, warm, desaturated, period. First you correct, then you grade.
Correction vs grading
| Color correction | Color grading | |
|---|---|---|
| Goal | A correct, natural image | An image with an aesthetic intention |
| What it adjusts | Exposure, white balance, contrast, saturation | Overall tone, shadow and highlight colors, style |
| Order | First | Second |
| Example | Removing the green tint from a fluorescent light | Giving a memory a warm, nostalgic tone |
Read the scopes, not the screen
Your monitor may be badly calibrated, and your eyes get used to any color cast within minutes. Scopes (the waveform monitor and the vectorscope) don't lie.
- Waveform: left to right is the image; bottom to top is brightness. Shadows shouldn't be crushed at 0 unless you mean it, and highlights shouldn't be stuck at 100.
- RGB parade: the same waveform split into red, green and blue. If something should be white or gray, the three columns need to be at the same height in that area.
- Vectorscope: shows which color the image leans toward and how saturated it is. Human skin, of any tone, falls close to the same line: the skin tone line.
A simple four-step workflow
- Normalize: if you shot in log, apply your camera's LUT or color space transform to Rec.709.
- Exposure and contrast: adjust blacks (lift), midtones (gamma) and highlights (gain) while watching the waveform.
- Balance: neutralize color casts with the parade; check that skin falls on its line.
- Look: with the image corrected, apply your intention in a separate node or layer.
In DaVinci Resolve each adjustment can go in a different node: one for exposure, another for balance, another for the look. That way you can disable or change one without breaking the others. In other editors, use adjustment layers.
LUTs: a tool, not a solution
- Technical LUT: converts your camera's log to Rec.709. It's published by the manufacturer. It's a starting point, not always the end.
- Creative LUT: applies a style. Use it after correcting, and at reduced intensity: a LUT at 100% on a badly exposed image falls apart.
A LUT expects an image exposed in a specific way. If your shot is dark, the LUT will leave it dark and with the colors off. Fix the exposure before the LUT.
Matching shots
Two shots from the same scene need to look as if they were filmed at the same moment. Choose a reference shot (the most important or the best exposed), correct it and bring the others toward it, comparing in split screen and on the scopes. Look at the height of the waveform, the position of the skin on the vectorscope and the color of the blacks.
Classic looks and how to get them
| Look | How it's done, in general |
|---|---|
| Warm and nostalgic | Midtones toward orange, saturation slightly low, blacks lifted a little |
| Teal and orange | Shadows toward blue-green, skin toward orange: a complementary contrast widely used in commercial cinema |
| Cold and clinical | Midtones and highlights toward blue, low saturation, high contrast |
| Desaturated documentary | Reduced saturation, moderate contrast, natural skin |
| Matte | Lifted blacks (they don't reach 0) and soft contrast |
- Correct first, grade second.
- Trust the scopes, not the screen.
- Skin has its own line on the vectorscope.
- Use LUTs on images that are already correctly exposed.
- Choose a reference shot and match the others to it.
Your turn: correct and match three shots
Choose three shots from the same scene filmed in slightly different light.
- Correct the best one while watching the waveform and the parade.
- Match the other two to it.
- Duplicate the timeline and apply two different looks. Pick one and explain why.