The science of color is a multidisciplinary field that explores the physical, physiological, and psychological aspects of color. It encompasses a range of disciplines, including physics, chemistry, biology, psychology, neuroscience, and art.

At its core, the science of color is concerned with understanding the nature of light and how it interacts with matter to produce the colors that we see. This involves studying the properties of light, such as wavelength and frequency, as well as the properties of materials that interact with light, such as pigments and dyes.

In addition to the physical aspects of color, the science of color also explores how humans perceive and interpret color. This involves studying the physiology of the human eye and brain, as well as the cultural and psychological factors that influence how we perceive and assign meaning to different colors.

Overall, the science of color is a fascinating and complex field that touches on many different aspects of the natural world and human experience. It has practical applications in fields such as design, art, and medicine, and continues to be an active area of research and exploration.

https://library.si.edu/exhibition/color-in-a-new-light/science

The relative shade of a color refers to its level of darkness or lightness in comparison to other colors. This is often referred to as the color's "value" or "brightness". For example, a lighter shade of blue would have a higher value than a darker shade of blue. The relative shade of a color can be adjusted by changing its saturation or by adding black or white to it, which respectively decreases or increases its brightness.