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Yellow in Color Printing and On A Computer Screen

In color printing, yellow is one of the three colors of ink, along with magenta and cyan, which can be overlaid in the right combination, along with black, to print any full color image. (See the CMYK color model).

The yellow on a color television or computer screen is created in a completely different way; by combining green and red light at the right level of intensity. (See RGB color model).

In technical terms, electric yellow' is the most intense yellow representable in 8-bit RGB color model; yellow is a secondary color in an additive RGB space.

The measured light spectrum from yellow pixels on a typical computer display is complex, and very unlike the reflectance spectrum of a yellow object such as a banana.

Process yellow (also known as pigment yellow, printer's yellow or canary yellow) is one of the three colors typically used as subtractive primary colors, along with magenta and cyan. The CMYK system for color printing is based on using four inks, one of which is a yellow color. This is in itself a standard color, and a fairly narrow range of yellow inks or pigments are used. Process yellow is based on a colorant that reflects the preponderance of red and green light, and absorbs most blue light, as in the reflectance spectra shown in the figure on the lower right.

Because of the characteristics of paint pigments and use of different color wheels, painters traditionally regard the complement of yellow as the color indigo or blue-violet.

Process yellow is not an RGB color, and there is no fixed conversion from CMYK primaries to RGB. Different formulations are used for printer's ink, so there can be variations in the printed color that is pure yellow ink.

The first recorded use of canary yellow as a color name in English was in 1789.

• Color printing typically uses ink of four colors: cyan, magenta, yellow, and key (black). When CMY “primaries” are combined at full strength, the resulting “secondary” mixtures are red, green, and blue

• Mixing all three theoretically results in black, but imperfect ink formulations do not give true black, which is why an additional K component is needed.

• An example of color printing from 1902. Combining images in yellow, magenta and cyan creates a full-color picture. This is called the CMYK color model.

• On a computer display, yellow is created by combining green and red light at the right intensity on a black screen.This is called the RGB color model.