Colorfulness

Colorfulness, chroma, and saturation are ways we talk about how bright and lively colors look. They help us understand why some colors seem more vivid and rich than others.

Colorfulness is how much a color stands out from gray, white, or black. It depends on the color of an object and how strong the light shining on it is. The brighter the light, the more colorful the object usually looks.

Chroma tells us how different a color is from a gray of the same brightness. It focuses on the object’s own color. Saturation describes how “pure” a color looks compared to its brightness. An object’s saturation stays about the same unless the light is very bright.

These ideas help scientists and artists understand and measure colors better. They are used in systems like the Munsell system to describe colors in a way that matches how we see them. Knowing about colorfulness, chroma, and saturation can help you see the world in a new way.

Chroma

See also: Psychophysics

Chroma is a way to measure how strong a color looks. It tells us how much color there is compared to a plain shade like white or gray. In some systems that help us understand colors, chroma shows how much the color stands out.

When we use special tools to study how our eyes see colors, chroma can help us describe colors in a way that matches what we actually see. This makes it useful for understanding how colors look in different lighting or on different surfaces.

Saturation

Saturation tells us how strong a color looks. A highly saturated color is very bright and pure, like the light from a laser. If we make a color lighter or darker, its saturation goes down. We can also make a color less saturated by adding white, black, gray, or its opposite color.

There are different ways to measure saturation. In some systems, it depends on both the color’s strength and its brightness. In other systems, like HSL, saturation can stay high even when the color is very light or very dark.

Excitation purity

The excitation purity of a color shows how different a color is from a neutral white color. We find this by looking at where the color sits on a special diagram. We then compare this to where the white point is and the farthest point on the diagram that has the same dominant wavelength. This helps us see how "pure" or strong a color looks when compared to white.

Different ways to describe colors may give different numbers for excitation purity, but they all try to show how much a color stands out from neutral white.