Friday, May 7, 2010

Spot Colors

In offset printing, a spot color is any color generated by an ink (pure or mixed) that is printed using a single run.

When your job requires color, you have two options: four-color process and match, or spot, colors. Four-color process work involves the printing of cyan, magenta, yellow, and black halftones, one over the other, at slightly different angles to simulate the full color gamut. For a photograph, this usually works well.

Sometimes, however, the four process colors don’t capture the intensity or specific color you want in a certain location within a photo. In cases like these, you can add a “touch plate” of a fifth color (called a spot color) to accentuate specific areas. (A spot color -- Trumatch, Pantone or PMS, Focaltone, Toyo, etc. -- is created from other colors combined to make a homogeneous mixture, in the same way that you might mix flour and baking powder when baking. Once mixed for your printer, your spot ink is a single color, unlike the screens of cyan, magenta, yellow, and black laid over one another to create four-color work.) Let’s say you’re printing a photo of a bouquet of flowers, for instance, and you want the rich reds to stand out dramatically. In this case, you might add a touch plate of a fifth color, a PMS red, to bring out the red areas within the flowers. The color will only print in a few areas. It may be subtle, but quite effective.

Another instance where you might want to use a spot color is when your project includes your company logo. Let’s say you’re printing a four-color brochure that includes several full-color photos, some text, and your company logo. It’s quite possible that you could use the four process colors and get a perfectly acceptable product. (To get a preview of what the finished product will look like, you can check a Pantone process-color to match-color swatchbook, which shows the nearest possible process color build percentages used to duplicate a PMS color.)

But let’s say your company logo is made up of colors that cannot be adequately represented within the process color gamut.

Suppose you want to build a particular red that matches the PMS 199 of your logo, but it appears a little muddy. Or you want to build a particular blue that matches the PMS 286 of your logo, but it is a little drab when compared with the actual Pantone colors the designer of your logo had in mind. Or, worse, what if there is a variation on press, so that in the course of the press run the colors of your logo shift slightly away from the colors you expect? Perhaps the printer makes a judgment call to bring the flesh tones in the company photos back in line, and the colors in your logo shift dramatically in the process. What can you do?

Hopefully, your job is already on a five- or six-color press. If so, your incremental cost to add an extra spot color should not be that high, and your control over the colors in your company logo will improve significantly. If your printer is running the job on a four-color press, however, adding a match color will be considerably more expensive. It will require taking the job off press after printing the four process colors, washing up the press, and then running the job through the press again to print the match color once the process inks have dried. In this case, you might want to stick with the four-color process option and skip the extra PMS color to avoid a large price increase. The good news is that more and more printers have multiple-unit presses (five-, six-, or even eight-unit presses) that will allow the cheap addition of match colors. It would be prudent to discuss these various scenarios with your prospective printers before deciding which printer to use.