Overview
"Hue vs. Lum" (Hue versus Luminance) is not a light or grip equipment, but a tool from digital color correction (Color Grading). It is one of the so-called HSL custom curves, prominently featured in DaVinci Resolve and in a comparable form in other grading applications (e.g., Adobe Premiere Pro via Hue/Saturation curves).
The curve allows for selective adjustment of the luminance (brightness) of a specific hue range, without altering the hue itself or affecting other colors in the image. The horizontal axis represents the color spectrum (Hue), and the vertical axis represents the luminance of the respective hue.
How it Works
One or more control points are set on the curve for the target hue and then adjusted:
- Point Upwards: The selected hue becomes brighter.
- Point Downwards: The selected hue becomes darker.
The difference from the related "Hue vs. Sat" curve lies in the property being manipulated: Luminance describes how much black or white is mixed into a hue, while Saturation indicates how pure or how much gray is mixed with the hue.
Control points can be set either via the Hue icons below the curve (broad, coarse selection) or more precisely by clicking a pixel directly in the preview image, which creates a sharply defined point on the exact hue.
On-Set or Post-Production Use
Hue vs. Lum belongs to secondary color correction and is used in post-production, not on location. Typical applications:
- Darkening individual hues to enhance depth and saturation effects (saturated primary colors like pure red, green, or blue appear more naturally darker).
- Brightening colored image elements to draw attention to them.
- Correcting skin tones, such as selectively brightening reddish facial areas.
Practical tip: Since the tool isolates only a narrow hue range, strong adjustments can result in visible noise or an unclean look. An HSL qualifier with a luminance channel limit often serves as an alternative.
Related HSL Curves
| Curve | Effect |
|---|
| Hue vs. Hue | Shifts a hue to another hue |
| Hue vs. Sat | Adjusts the saturation of a selected hue |
| Hue vs. Lum | Adjusts the luminance of a selected hue |
| Lum vs. Sat | Adjusts saturation based on luminance |
| Sat vs. Sat | Adjusts saturation based on existing saturation |