Inspector Gadgets

A sampling system, Shumaker said, uses a CCD, 3-chip color camera, which moves back and forth over the web, covering 100 percent of the web, but not 100 percent of the time. "The typical sampling system will only inspect approximately 3 to 10 percent of the total printed production," said Manning. "These web sampling systems will eventually inspect the entire pattern that is repeated, but not every segment of the web," and not immediately, added Stern. "Up to 100 percent of the surface is checked, piece by piece, or sampled," Stern explained. "Typically, each piece is inspected in one to five seconds. An entire 100 percent of the surface would take typically two minutes."