colorsluminance
Colorsluminance refers to the perceived brightness of a color. It is a critical component in understanding how we see and interpret the visual world, distinct from hue (the pure color itself, like red or blue) and saturation (the intensity or purity of the color). Luminance is not an objective measure of light intensity, but rather a subjective perception influenced by the human visual system. Different wavelengths of light are not perceived with equal brightness, even if their physical intensity is the same. For example, green light is generally perceived as brighter than blue light at the same physical intensity.
In color models, luminance is often represented as a third dimension alongside hue and saturation. For instance,