Additive primary colors

Additive primary colors are colors which produce the color white when added together. The additive primary colors are red, green and blue. Colors in the additive color system are produced from the combination of different intensities of red, green, and blue light. A complete absence of all additive primary colors appears black, while equal intensities form white. This system is essentially the opposite of the subtractive color system, which produces black when equal intensities of its primary colors are mixed.

Production of Additive Color
Visible Light is the portion of the electromagnetic spectrum that can be perceived by the human eye. The visible light spectrum consists of wavelengths that produce colors from violet (~400 nm) to red (~700 nm). However, red, green, and blue wavelengths are considered the primary additive colors because combinations of these colors can produce almost any other color. When equal parts of each of the three primary colors are combined, the result is white light. The complete absence of the three primary colors results in no color, or black. According to the Media College, " Additive primaries describe the colours we see in the real world, created by light".

When only two primary colors are combined, each at full intensity, it creates an additive secondary color. The secondary colors are cyan, magenta, and yellow. By changing the intensity of the primary colors, most of the other colors can be produced. These are some of the possible combinations that create new colors.

Red + Blue = Magenta, Red + Green = Yellow, Blue + Green = Cyan, Red + Blue + Green = White.

Additive colors are created by anything that emits its own light source, whereas subtractive primary colors are used when light is being absorbed and reflected. One of the more important applications of additive color is in projection technology, such as television or in computer monitors. These technologies use the RGB color model in order to produce many of the different colors on the spectrum. Each pixel has three sub pixels that emit red, green, or blue light. By changing the intensity of each sub pixel, each pixel emits a color that forms the display.

Cartographic Application
Additive primary colors are used when working with maps on a computer screen, but when the map is printed on a medium, subtractive primary colors are formed from the ink. It is important to take this into account when planning map design because subtle color changes could occur as the additive primary colors on the screen are converted to subtractive primary colors on printed paper. This could alter the effectiveness of the color scheme of the map. James Clerk Maxwell is said to be the father of additive colors.