What is CMYK Color?
CMYK color stands for cyan (C), magenta (M), yellow (Y), and black (K for “key”), and is the color mode used by commercial printing equipment to create full-color graphics and images. The printing process involves combining varying amounts of the different color inks to produce a full spectrum of color. The “K” representing black, for “key”, refers to the printing plates being keyed, or aligned, to the the black printing plate. CMYK color is also called process color, or four-color process.
What is RGB color?
The other common color mode, RGB color, uses three colors – red (R), green (G), and blue (B) – to create a full-color effect. RGB is the color mode used by screens, including computer monitors, digital cameras, and televisions. Varying levels of red, green, and blue light combine to create the images that appear on the screen. That’s why web-based images are created in RGB color mode.
What is a Pantone Color?
Pantone is a company that specializes in products that accommodate color matching, called the Pantone Matching System, or PMS for short. Is there a specific shade of orange or blue that is included in your logo? For consistency, you want to make sure your brand colors are the same on every marketing project, so selecting a PMS color for those hues is important. Pantone sells swatch books with formulas for color so that every printer around the world can match their ink to a Pantone color. Pantone colors are also referred to as spot colors.
Viewing either PMS or CMYK colors on a computer screen is a challenge due to lighting changes and display variations (displays use the RGB color model). Pantone swatch books and color charts for PMS colors allow anyone to see the exact color that will be printed on your project. A unique set of numbers assigned to the colors allows printers and customers to communicate effectively about what can be a challenging and variable subject: color. What looks like magenta to one person could easily be described as a red-purple by someone else — making it tough to describe specific colors without the common language available with PMS standards.
Printing CMYK versus Pantone Colors
Printing CMYK Colors
To create an image using CMYK colors, printers define four separate printing plates that combine together in dot patterns to make up a full image. One plate is used for each of the four colors (cyan, magenta, yellow, and black) and is designed to lay down a very specific amount of pigment on the image. While this may sound like a simple way to print, it has worked effectively for hundreds of years.
Printing PMS Colors
PMS colors are slightly different than CMYK colors because they are mixed before they are applied to a plate surface. The pure spot color, or PMS color, is a mixed ink that allows for a wider range of reproduced colors than the CMYK spectrum. PMS inks are not laid in a dot pattern but can be screened in a halftone to produce a variety of shades.
Color Mode for Print
When designing artwork for print, it is recommended to start your design in CMYK color mode to help ensure your images and colors are accurate from the start. If artwork intended for print is in RGB color mode, it will need to be converted to CMYK color mode before going to print.
While most colors translate fairly well from one color mode to the other, subtle color shifting is common when converting from RGB to CMYK (and vice versa), requiring some manual adjustments to get things just right. For example, some software will translate a 100% blue RGB value into a CMYK color that looks more purple than blue. Such changes will need to be accounted for if you start with an RGB color mode and then convert to CMYK color mode later on.
Because of the different color modes between screens (RGB) and print (CMYK), it is important to view a printed proof of a project before it goes to print on a press to ensure color accuracy.
Converting Color in Adobe Photoshop
- Create a copy of your original image and open both the original and the copy in Photoshop. This will provide you with a point of reference to look back on once you’ve converted your image to CMYK.
- Choose the copy you want to convert and select Image > Mode > CMYK Color from the main toolbar at the top of the screen. This will convert the image to CMYK color mode.
- Refer back to your original image (still in RGB mode) as a color reference, and adjust any colors in your new image as needed. In most cases, Photoshop will do a good job converting colors in the file, but subtle adjustments may be needed.