Trapping

Trapping helps to avoid the unwanted white gaps as seen in bottom example.What is trapping? Trapping digital files is the process of compensating for misregistration on the printing press by printing small areas of overlapping color where objects meet.
Huh? If you've always worked with a desktop printer or strictly one color jobs you may not quite understand register or close register or the need for trapping and how it affects your final printed job.
When you print from your color inkjet printer the color is all applied at once. Each color generally ends up just where you expected. It doesn't work that way on a commercial printing press. When your document consists of more than one color of ink the page may have to pass through the printing press two or more times as each color is applied to the paper.
Presses aren't perfect. They run at incredibly fast speeds. Sometimes the paper or the plates applying the ink may shift. It might be a tiny, tiny little shift -- but it can throw off your design enough to be noticeable. For example, a white gap may appear between a green letter that is supposed to be touching a blue box. When this happens your color is out of register -- things just don't align properly.
So how do you prevent having your work come off the printing press out of register? By avoiding the need for trapping. The best alternative to trapping is to simply print using all one color or never allow your colors to touch or get too close.Explore other alternatives to trapping.

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