Extend Colors to Extend Reach
Extended Color Printing— Why CMYK+Spot Won’t Always SufficeNovember 2009 by Jean-Marie Hershey
Of all the assets associated with a given brand, color is arguably the most identifiable. And not just any color, but rather the intense, vibrant color that differentiates a company from its competition and is a key component of high-impact graphics designed to grab the consumer's attention and hold it long enough to trigger a purchase decision. Any technology that can make this happen without incurring the expense of additional prepress work or multiple passes through the press will be of special value to profit-minded printers and their price-sensitive customers.
Transcending the limits of CMYK
The fact that the CMYK color space is significantly smaller than the color space visible to the human eye underscores the limitations of 4-color process printing in color-critical applications like fine art and packaging. Violets, greens, and oranges, for example, are very difficult to match using 4-color process. With its limited gamut and ability to simulate only about 60 percent of standard Pantone colors, therefore, the 4-color process system based on CMYK alone packs insufficient marketing punch for many packaging applications. At the same time, working with spot colors can be time-consuming and costly. A more visually and emotionally satisfying—and potentially more cost-effective—option is to add two or more special colors to the standard 4-color set to extend the color gamut and enable the press to print a wider range of colors.
Extended gamut color sets like Hexachrome, Opaltone, and FMsix are defined and distinguished by the differences in overall gamut size when compared with CMYK. "With CMYK, there is only so much color available to produce spot color matches because you are limited to the overprint combinations of these four colors," says Scott Thompson, director commercial technology for Southern Graphic Systems (SGS, www.sgsintl.com). "By adding additional colors, the color space is expanded, and there are more color combinations and more opportunities to match colors that are unattainable with CMYK alone. This is especially beneficial when you look at the more difficult colors to match (like oranges, purples, and greens), which is why many of the ink sets are in this color family."
For the printer/converter, using one set of inks can effectively simulate a vast number of spot colors1 while reducing the number of press runs, wash-ups, and inks involved. Fewer changeovers also yield greater consistency over the length of the print run. For the end user/CPC, the payoff comes in the form of dramatic visual shelf impact that translates into dollars at the cash register.