Understanding Colour

What is Colour?

Color is all around us. It is a sensation that adds excitement and emotion to our lives. Everything from the clothes we wear, to the pictures we paint revolves around color. Without color; the world (especially RGB World) would be a much less beautiful place. Color can also be used to describe emotions; we can be red hot, feeling blue, or be green with envy.

In order to understand color, we need a brief overview of light. Without light, there would be no color, and hence no RGB World.

Light is made up of energy waves which are grouped together in what is called a spectrum. The light that appears white to us, such as light from the sun, is actually composed of many colors. The wavelengths of light are not colored, but produce the sensation of color.

Visible light –

The wavelengths our eyes can detect is only a small portion of the electromagnetic energy spectrum. We call this the visible light spectrum. At one end of the visible spectrum are the short wavelengths of light we perceive as blue.

At the other end of the visible spectrum are the longer wavelengths of light we perceive as red. All the other colors we can see in nature are found somewhere along the spectrum between blue and red. Beyond the limits at each end of the visible spectrum are the short wavelengths of ultraviolet light and X-rays and the long wavelengths of infrared radiation and radio waves, which are not visible to the human eye. The human eye is highly sensitive to color. It can distinguish millions of colors.

If the visible portion of the light spectrum is divided into thirds, the predominant colors are red, green and blue. These three colors are considered the primary colors of the visible light spectrum.

Primary colors can be arranged in a circle, commonly referred to as a color wheel. Red, green and blue (RGB) form a triangle on the color wheel. In between the primary colors are the secondary colors, cyan, magenta and yellow (CMY), which form another triangle.

The media and methods used to reproduce color include color paintings, printing presses, color film, color monitors, color printers, etc.