HLS Secondary Keying

color correction technique used to refine a chroma key, particularly when dealing with poor-quality green or blue screens. It involves using the HSL (Hue, Saturation, Luminance) parameters as a secondary qualifier within a color tool to isolate and manipulate a very specific color range. This allows an editor to clean up spills, uneven lighting, or color variations in the background that a primary keyer fails to remove cleanly.