CMYK, RGB, PMS: Color Systems Defined

Frequently, we get requests for logos, photos or other artwork to be used in ads, web sites, reviews, magazines, etc. Often we don’t know the application, we just hear: “Can you send that photo?” Usually our next question is about how the image will be used. The reason we ask is that the correct type of file, including color type, is dependent on the application. Below is a basic explanation of the different color systems.

PMS = Pantone Matching System

The Pantone Matching System is a system of thousands of numbered swatches. Most corporate colors, in a logo for example, are identified with a number from this system. You’ll often hear it referred to as a PMS number. Pantone colors are also called “spot” colors.

This is similar to picking paint at the hardware store to paint your walls: You refer to swatches, choose by number and then the color is pre-mixed before application. This is good for applications that are predominantly one color (or two) such as a business card.

Printing a 1 or 2 color job can be less expensive than a 4-color job because there are fewer printing plates made. This system also creates the most accurate color match and the sharpest details.

CMYK = Cyan, Magenta, Yellow, Black. Also called 4-color, or process

CMYK refers to full color printing. Note: because of the potential confusion with the words and abbreviations for blue and black, blue is called cyan and abbreviated C, and black is abbreviated K.

While using PMS colors is best for something that prints in limited colors, imagine if you had to pre-mix each color used within a photograph. It would be nearly impossible. Instead, the CMYK or Four-Color process is used. For every possible shade and color, this process determines the percentages of each of the four colors (CMYK) needed to make that color.  This is then translated into very small dots. The human eye blends these colors together to see the full spectrum of color.

CMYK is used whenever there are full color images, or when the number of colors makes it more practical than using just PMS colors. CMYK is also the primary system for digital printing, as specific pantone colors can not be put into a inkjet or laser printer.

Full color, offset (professional) printing is always CMYK. However, a large press can accommodate the four colors of cyan, magenta, yellow and black plus additional Pantone colors if necessary. Sometimes that is done if there are photos that require CMYK, but a logo that prints best used the actual Pantone ink. In that case, it would be called a five color print job.

RGB = Red, Green, Blue

RGB is the color system for computer monitors, video, etc. Without going into the science, it is critical to understand that PMS and CMYK are for printed pieces and RGB is for computer applications such as web sites.

Web Safe colors are a sub-set of 216 RGB colors that accurately display even on monitors with a very limited spectrum of colors. These days, most computer monitors have better video cards and higher resolution and can view more than this limited palette. However there are still some web-based design code that prefers these colors.

Finally, it’s important to note that while these are called “safe”, that does NOT mean a color will look the same from one monitor to the next. Variability with screen brightness, lighting conditions, and hue & contrast settings will render the exact same color differently from one computer monitor to the next.

For reference, Visible Logic’s green is: r140 / g198 / b63. This is also given a hexadecimal number of: 8cc63f You can see that green in the logo at the top of this web site.

Always provide the right file

Always try to provide the correct file type and color profile for the intended application. This will ensure the most accurate color and avoid problems.

While Visible Logic, and many of your vendors, can switch a file from one color format to another, some systems cannot handle an incorrect format and files may render incorrectly or not at all.

When developing a new logo or branding identity it is best to define your color in all three colors systems. For example, Visible Logic’s logo is: PMS376  green; or 50%cyan/0magenta/100%yellow/0black; or r140 / g198 / b63. If required to use a web safe color, I use #669900.

Keep in mind that some colors translate more easily across systems, than others.

This topic of color systems was covered in my Graphic Design 101 presentation. If you found this helpful, you may want to read and download that entire presentation which also covers, typography, file types, layout, hierarchy, etc.