Do You See What I See?

Our eyes have the ability to discern thousands of different colors in the visible spectrum; many more colors in fact, than can be reproduced on a computer monitor, ink jet or laser jet printer.  And more colors than can be reproduced via commercial printing processes. Monitors, scanners, desktop printers and commercial presses all have different ways of "describing" or interpreting color; this is why the image you see on your computer screen may not look the same as a printed sheet.Color variations occur from monitor to monitor, and between monitors, ink jet prints and commercially printed pieces.

Monitors display color based on combinations of light, known as "additive color". RGB or Red light, Green light, and Blue light, at equal intensity or brightness, combine on your monitor to make white light. Take a magnifying glass and look very closely at this screen, look at the image shown in this paragraph. If you are looking close enough you can see rows and rows of tiny dots. Each dot is either red, green, or blue. Move the magnifier to different areas and notice which color dots are brighter and darker. Now, back away from the monitor and note the color represented in the image when viewed from a distance. Look closely again at the yellow color and move in to see the individual dots only where the screen is yellow. You should see only red and green dots. The blue dots are very dark with only a little light illuminating each blue dot, so when viewed from a distance the red and green dots combine to make yellow.

Recall the variations in color and picture quality you've seen at your local electronics store. Lined up side by side and tuned to the same channel, television sets of all makes and models, old technology and new are represented. The color differences from one to another are easily noticeable—the same is true when viewing images on different computer monitors, such as yours and ours, and in printing.

CMYK & Process Printing

Offset or Process printing produces prints utilizing the colors Cyan, Magenta, Yellow, and blacK, commonly refered to as CMYK or "Subtractive color". Color is reproduced using transparent cyan, magenta, yellow, and black inks. When 100% each of cyan, magenta , and yellow are combined together the result is dark brown/gray, nearly black. Black ink or K, is added to intensify dark colors.

To illustrate this concept, imagine having 4 sheets of transparent plastic,one in each of the four colors. Place the cyan, magenta, and yellow sheets each stacked one on top of the next. The overall color of the stack would be a muddy brown or gray. "Subtract" (remove) the magenta sheet from the stack, leaving the cyan and yellow sheets. Together cyan and yellow combine making green. Add the transparent black sheet and the result is a darker green.