Color is an interesting element of graphic design because it can be applied to any other element, changing it dramatically. It can be used to make an image stand out, to show linked text on a website, and to evoke emotion. Graphic designers should combine their experience with color with an understanding of color theory.
The HSV color space is important to look at because it describes color based on three properties: Hue, Saturation and Value. As you edit these values, the full spectrum of colors can be created.
There are many models used to measure and describe color. The RGB color model is based on the theory that all visible colors can be created using the primary additive colors red, green and blue. These colors are known as primary additives because when combined in equal amounts they produce white. When two or three of them are combined in different amounts, other colors are produced. For example, combining red and green in equal amounts creates yellow, green and blue creates cyan, and red and blue creates magenta.
The CMYK color model is used in the printing process. When two RGB colors are mixed equally they produce the colors of the CMYK model, known as subtractive primaries. Green and blue creates cyan (C), red and blue creates magenta (M), and red and green creates yellow (Y). Black is added to the model because it cannot be created with the 3 subtractive primaries (when combined they create a dark brown). The K, or “key,” stands for black.
When designing for print, a common issue that has to be dealt with is the difference between the color on your computer display and on paper. Even if your monitor is calibrated correctly the match them as best as possible, your client’s will not be, and so a third “version” of the color comes into play. If you then print proofs for your client on any printer other than the one that will be used for the final job (which is often the case), more colors join the mix that won’t match the final piece.
Color separation is the process by which original artwork is separated into individual color components for printing. The components are cyan, magenta, yellow and black, known as CMYK.