Pure color information independent of brightness and saturation — the actual color itself. Critical in grading to shift color casts without touching contrast or luminance.
On set or in the edit, you deal with three separate color dimensions daily — hue, saturation, and brightness. Hue, in this context, is the pure wavelength: red stays red, blue stays blue, no matter how dark or gray it gets. In a practical workflow, this is crucial because you can correct a color cast — like an unwanted green cast under LED light — without simultaneously destroying your contrast.
In color correction, you work with hue sliders that rotate the entire spectrum. The classic tool: the Hue/Saturation slider in DaVinci or Lumetri. You turn the hue value a few degrees, and all pixels in that color range shift on the color wheel — red becomes orange, green becomes cyan. This is completely independent of how bright or dark the area is. This way, you can specifically warm up a skin tone without affecting the shadows, or warm up the sky blue from within without touching saturation or contrast.
Practically speaking: When you're mixing a scene on set — artificial light on a windowsill with daylight — hue differences between the light sources often arise. The one-million-Kelvin difference isn't simply solved by making it brighter or darker; you have to shift the hue itself. With targeted hue adjustments in specific color channels (red, green, blue, cyan, magenta, yellow), you reduce these tensions without losing image depth.
In the context of a color grading pipeline, hue often comes after the rough luminance adjustments. First, you set your exposure, your gamma, and your contrast, then you fine-tune with hue, saturation, and very subtle brightness moves. This way, you retain maximum control, and the image looks — not cobbled together.