Internet Colors - Set of 1035

Non-photo Blue Color 632 - #A4DDED

Non-photo blue is a particular shade of blue that can not be detected by graphic arts cameras. This allows layout editors to write notes to the printer on the print flat (the image that is to be photographed and sent to print) which will not show in the final form. As well as this, it allows artists to lay down sketch lines without the need to erase after inking.

As of late, with digital scanning and image manipulation, non-photo blue fulfils its function in a different way. The artist can do his or her sketch and inking in the traditional method and scan the page. Most scanners will detect the light blue lines. However, shifting to greyscale and increasing the contrast and brightness will cause the blue to disappear. Another common approach involves replacing the blue channel with another channel – typically the red channel. The exact processes may differ depending on the scanner, settings and image-editing software, but the concept remains the same.