The ultimate color guide

four-color process printing ink

When we think of color, it's helpful to think of spectrums. The visible spectrum contains all of the colors you can see (as represented by the “eye” icon on the chart shown). The RGB spectrum is comprised of the colors that can be displayed on a monitor. The printable spectrum represents the colors we can print using a specific printing process — called “four-color process — or CMYK — cyan/magenta/yellow/black. The printable spectrums are different for desktop color printers, offset presses and commercial digital presses. Adding a spot color (special mix ink) increases the printable spectrum.

The vast majority of printed products — including mass-produced items and large format items — are produced with four-color process. Some colors, such as vibrant oranges and greens — and/or metallic colors — simply cannot be produced in this manner. This is where special mix/spot color/Pantone colors come in.

PMS printing ink

PMS stands for "Pantone Matching System". It is a system with hundreds of colors specified and defined — with books that have been produced with these colors. There's also a book available called the Color Bridge that shows all of the PMS colors and the closest four-color process equivalent. Looking through the book you can see that perhaps 80% of the colors can be matched very closely with four-color process and somewhere between 10% and 20% can't be matched closely at all.

Some organizations select a PMS color as part of their corporate identity, which requires that the actual PMS Ink is used when printing their material. For example, there is no way to closely simulate a metallic pantone color, using four-color process. This is the reason we have five and six color printing presses: we can print four-color process for most of the art and copy and photographs, and then add a special mix/spot color color for an organization's specific brand color. Quite often when printing large areas of solid PMS color, printing companies will apply the same color twice in two different print units; it's called a double bump.

monitors and color

Monitors and desktop printers are impossible to completely calibrate for accurate color representation. Monitors live in an RGB color space — print is CMYK (four-color process) — and desktop printers (including some high-end models) simply don't have the ability to reproduce tightly calibrated color standards. We use Gracol 7, a calibration and certification by a third party licensed to do so, and rely internally on expensive calibration tools to keep our proofing devices and presses in sync.

in Basics

The ultimate color guide

four-color process printing ink

PMS printing ink

monitors and color

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