The classification of black and white as colors or shades depends on the context: light physics or art pigment. While they are widely accepted as colors in everyday language, the scientific definition of color is tied to specific wavelengths of visible light. Understanding this difference requires separating light emission from the principles of reflection and absorption.
Black and White in the Science of Light
The definition of color in physics uses the additive color model, which describes how light mixes. This model, often called RGB (Red, Green, Blue), is used by electronic screens and defines color based on the presence of specific light wavelengths.
White is the result of combining all wavelengths of visible light at maximum intensity. A white surface reflects nearly all light striking it back to the observer’s eye. Although white contains the full spectrum, it is not a singular spectral color like blue or green.
Black is the total absence of visible light. A black object absorbs all light wavelengths, reflecting none, resulting in zero light energy being perceived. Since color is a measure of light, black is scientifically defined as the absence of color.
Black and White in Pigment and Art
In contrast to light physics, the subtractive color model governs how pigments, such as paints and dyes, create color. This model is called subtractive because pigments absorb certain light wavelengths while reflecting the remaining ones. This is the context most people experience when painting or printing.
In this system, white is considered the base, reflecting all light, similar to a blank sheet of paper. White pigment is often used to lighten other colors, acting as a neutralizer. Maximum light reflection occurs due to the absence of pigment.
Black pigment is produced by mixing the subtractive primary colors: cyan, magenta, and yellow (CMY). When mixed, these pigments ideally absorb nearly all light, resulting in black. Because impurities often result in a muddy dark brown, a true black pigment (Key, or K) is added to the CMY set to create the CMYK used in printing. In art and printing, black is treated as a necessary and functional color for mixing and achieving depth.
Defining Hues Shades Tints and Tones
Color theory clarifies the terminology used to define black and white. A hue is the purest form of a color, corresponding to spectral colors like red, blue, or yellow; black and white are not considered hues.
Tints, shades, and tones are variations created by adding black, white, or both to a pure hue. A tint is created when white is added, resulting in a lighter, less intense color, often called a pastel. This process lightens the color’s value.
A shade is created by adding only black to a pure hue, which darkens the color without changing its fundamental color family. Black is the component used to create shades of other colors. A tone is produced when a hue is mixed with gray, a combination of black and white, making the color less vibrant.
In the practical world of art, black and white are classified as neutral colors. They are indispensable for creating the depth and variation necessary to move beyond pure hues.