You may have seen the four colors used in commercial printing before: Cyan, Magenta, Yellow, and Black. This is commonly referred to as CMYK. (“K” is used for black to avoid confusion with blue).

But why those four colors? Aren’t we told in elementary school that the three primary colors are red, blue, and yellow?

Well, yes and no. Cyan and magenta are basically blue and red shifted slightly to adjust for the highest possible combination of colors and more vibrant hues. CMYK inks or toners are translucent dots layered over each other, like sheets of colored film. Red and blue are fairly dark colors to start with, so when they’re placed atop one another, the resulting purple is nearly black. Greens that use cyan are brighter, too, as are orange hues created with magenta.

Cyan, magenta, and yellow provide the widest available spectrum of color using only three inks. Black is used to create richer dark hues and true blacks, since cyan, magenta, and yellow can look a bit washed out on their own.

So why three colors plus black? Why not four, or five? Ink is costly, and three is the minimum number of inks able to achieve most colors. Some modern printers do add additional inks to achieve a wider range of color, such as a bright green and orange, or light cyan and light magenta.

If your print project is outside the color range of CMYK, or contains a metallic finish, you can use a “spot color”, which is a special single-color ink used as a separate layer in offset printing presses. Pantone is the industry standard system for spot colors.

But computer monitors and televisions use RGB (red, green, and blue).
How does that work?

Mixing light (digital media) is different than mixing ink or paint (printed media). Blending paint pigments creates darker colors, while blending light actually gives the illusion of removing color. This has to do with how different substances absorb or reflect light.

Think of a prism. Light enters as pure white and is split into all the colors of the rainbow. RGB screens use this same theory in reverse. By adding together three colors on separate parts of the spectrum, it blends into white.

You can see the principle of a “prism in reverse” with Newton’s Color Wheel, a rigid circle which displays the various colors of the rainbow. When spun quickly, the colors appear to blend together and disappear, leaving only white. You can see one in action in the video below.

My print file is RGB. Do I need to convert it to CMYK?

Nope. Our prepress team and printing technology will convert the RGB to CMYK for the best possible translation into the available color range.

Even so, please be aware while designing your project that some RGB colors do not translate well to standard CMYK, particularly highlighter green or orange, and vibrant royal blues. However, spot colors and other methods can be used to achieve your desired result.

Contact us today to discuss the best way to bring your project to life in vibrant, accurate color!