Color Separation

What are CMYK color separations?

CMYK refers to the four ink plates used in some color printing: cyan, magenta, yellow, and key (black). The CMYK model works by partially or entirely masking colors on a lighter, usually white, background. The ink reduces the light that would otherwise be reflected.

How does color separation work?

About color separations When inked with the appropriate color and printed in register with one another, these colors combine to reproduce the original artwork. The process of dividing the image into two or more colors is called color separating, and the film from which the plates are created are called the separations.

Types of Separations

There are a handful of separation processes that screen printers use. Understanding the different types of separations, and the challenges they present, can help you execute successful separations on a routine basis. Common screen-printing color separations include:

  • spot color. The most common type of color separations used in screen printing is spot color separation. Spot color separations are done for vector images. While they are typically solid, spot color separations can include some halftone dots to create a shading effect. Spot color separations are usually created in CorelDRAW or Illustrator.
  • Four-color process. The four-color process uses halftone dots of CMYK — cyan, magenta, yellow and black — to create detailed, photorealistic images. These types of separations are usually done in Photoshop, and creating a process color separation and printing four-color process correctly can be tricky.
  • Simulated-process color. Like traditional four-color process separations, simulated-process color separations make use of halftone dots to create highly detailed or photorealistic images. The difference is that simulated process color separations utilize a range of ink colors. They tend to be more vivid than four-color process prints and can be printed on darker materials, unlike four-color process separations. Like four-color process separations, simulated-process color separations are done in Photoshop.
  • Index color. Index color separations use square pixels of the same size, rather than halftone dots, to create color shading. Performing and printing and index color separation can be easier to perform than process separations. However, it often takes more colors to create a photorealistic print. The separations are performed in Photoshop, but images can be easily transferred from other programs, such as CorelDRAW or Illustrator.