Ever wondered why colour, when printed, is never the same as viewed on screen? This is because the two viewing processes are different and use two separate colour models. Most of us expect a colour difference from the screen or device to the finished printed article.
The truth is that the two kinds of light important to a graphic designer are more easily reproduced in two models. The two crucial kinds of light are transmissive, as through film or onto a cathode ray tube, and reflective, as from the printed page.
Let us explore colour models a little further.
The perfect colour model for transmissive light is called ‘additive’ and has as its primaries red, green and blue light: RGB. The additive secondary colours are cyan, made by mixing equal quantities of green and blue; magenta, made by mixing equal quantities of red and blue; and yellow, made by mixing equal quantities of red and green. One hundred percent of each of red, green and blue light creates white. Lesser but equal amounts of red, green and blue light make shades of grey
The reflective model uses cyan, magenta and yellow (CMY) inks as primaries to create a full spectrum. Yellow and cyan make green; magenta and yellow make red; cyan and magenta make blue. All three at full strength make black, and lesser but equal amounts create shades of grey. When light falls on paper, the white parts reflect all light. Cyan ink absorbs red light but reflects blue and green light. Magenta ink absorbs green but reflects red and blue. Yellow ink absorbs blue but reflects red and green. Black ink absorbs all light and reflects no colour