Color theory is a quite a complicated subject, but even a basic knowledge of the principles involved can help you to use color more effectively in your work.
Color behaves in different ways. Light looks different to our eyes than mixtures of paints or inks, and this can create some confusion. As a graphic designer you have probably heard of the color modes known as "RGB," "CMYK" and "PMS," but do you know which model to use, and when?
The RGB (red, green, blue) color mode is most often used when working with light - images that will be displayed back-lit on a television or computer monitor, as is the case with video and web design. Because of the way that light is emitted, red, green and blue are the primary colors when working with light. If you look very closely at your television you will see that the colors displayed on your screen are made up of tiny red, green, and blue dots. When these three colors are mixed together equally they create white, and when none are present the screen appears black. This color model is known as "additive color", and in this method the secondary colors are cyan, magenta, and yellow.
Imagine yourself sitting in a dark classroom. The complete absence of light means that the wall across from you is black. Now, if the people sitting behind you were to turn on a red light, a green light, and a blue light, the lights would combine as follows:
Red and green make yellow light, green and blue combine to make cyan, and blue and red make magenta. When red, green and blue combine equally, they make white light.
CMYK (cyan, magenta, yellow, and black), sometimes referred to as "four color process," is more often used when applying ink or paint to a paper or canvas (though this is not ''always'' the case, particularly in large format printing. Always ask your printer how they want you to prepare your files. If you have have created an image in RGB when CMYK was needed, you can convert it from one color model to the other, but this can cause your colors to appear muddy and ). This color model is called "subtractive color". In this model the color does not give off light of its own, but reflects light from other sources. In this mode, white is the absence of color, and black is created by mixing the three primary colors in equal amounts.
To visualize this, picture yourself sitting in front of a white painter's canvas. If you were to paint overlapping circles of cyan, magenta and yellow, the colors would combine as follows:
Cyan and magenta mix to make blue, magenta and yellow mix to make red, and yellow and cyan mix to make green. Black is a mixture of all colors, and the white background is the blank canvas, with no paint (or ink) present.
When designing for print it is important to note that the actual printed colors will not look exactly the same as they do on your screen, since monitors display color in RGB format, not CMYK. A proper monitor calibration can help to create more accuracy between the colors displayed on screen and the printed results, but due to the different behaviors of light and ink it is not usually possible to display colors exactly the same way that they will appear in print. If color is critical for a project, it is best to get a match print proof from your printer.
Pantone Matching System (PMS)
The company "Pantone, Inc." developed the first ink matching system in 1963. This became known as the "Pantone Matching System" and is used to identify and accurately match colored inks on coated, uncoated, or matte stocks. Each of the 1,114 pantone (or "spot") colors is assigned its own formula to ensure color consistency from one print run – or even one print shop – to another. RGB and CMYK color models create a whole spectrum of colors by combining their primary colors, and because of this it can be difficult to reproduce a color exactly from one print job to the next. Pantone colors are specially formulated and matched against a printed swatch book to ensure color accuracy and consistency from one print run to the next.
The disadvantage to spot colors is that it can become rather expensive (and even complicated) to print as the number of colors increases. Each spot color requires its own ink, film, and plate, which can be costly. Printing 1 to 3 colors is generally reasonable, but most print jobs including over 4 colors tend to be printed in CMYK (four color process) to reduce costs.
I hope that this article helps you to better understand the different color models that you will encounter in your graphic design work, and which to use for what purpose. As always, it is best to check with your printer before you begin a project. Doing so can save you both time and money.
Copyright (c) 2009, Adrienne Turcotte, All Rights Reserved