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Display and output spot colors using Lab values

Some predefined spot colors, such as colors from the TOYO, PANTONE, DIC, and HKS libraries, are defined using Lab values. For backward compatibility with previous versions of Illustrator, colors from these libraries also include CMYK definitions. The Swatches panel lets you control which values, Lab or CMYK, Illustrator uses to display, export, and print these spot colors.

Lab values, when used in conjunction with the correct device profiles, give you the most accurate output across all devices. If color management is critical to your project, Adobe recommends that you display, export, and print spot colors using their Lab values.

Note: To improve on‑screen accuracy, Illustrator uses the Lab values automatically if Overprint Preview is on. It also uses Lab values when printing if you’ve selected Simulate for the Overprints option in the Advanced area of the Print dialog box.
  1. Choose Spot Colors from the Swatches panel menu.
  2. Do one of the following:

    • Select Use Standard Lab Values Specified By The Book Manufacturer if you want the most accurate display and output of colors.

    • Select Use CMYK Values From The Manufacturer’s Process Book if you want spot colors to match earlier versions of Illustrator.