To really understand how an image or color on your monitor to be transferred to your printer, you first need to understand the differences of how RGB and CMYK. How the primary colors are mixed and how the RGB and CMYK are almost exact opposites.

Mixing light and the pigment

Many of you know that RGB colors are made of red lights, green and blue. (Red, Green, Blue) is difficult to visualize the RGB colors and how they interact. For example, mixing red and green for yellow is unknown to many. On the other hand, mixing cyan and yellow pigment for green is learned at a young age. The confusion arises because we are mixing RGB light and the more we use, the brighter the image becomes, and that is what is called a “color system” additive “. CMYK (cyan, magenta, yellow and black – the K comes from key), on the other hand, is “subtractive,” so we use the more pigment, the darker the image will become.
All you portray, you scan or view on a monitor will be in RGB. To print an image, however you have to convert it to CMYK, but that conversion could cause problems because not all RGB colors can be recreated in CMYK, some are beyond the capabilities of pigment CMYK, and are known as “out of the range.”

Opposites

The nearest opposite to red RGB we can produce the pigment is cyan; for RGB green is magenta, and blue RGB is yellow. Attempts to reverse the colors in Photoshop to try this for yourself. To get the opposite of the color black (no light), we use white (no ink).

Printing limitations become apparent when we mix black pigment using cyan, magenta and yellow. In theory, the three inks should be mixed to black. The reality though is that the pigments are not strong enough to produce a pure black color, introduces a fourth color, black, to add density. In a color image is separated properly find many shades in CMY channels, but the color black appears only in shadow. Incidentally, the black ink is made using carbon, and the ink is cheaper to produce. It is preferable to use pure black ink to use a costly mixture of cyan, magenta and yellow.
It is tempting to use the RGB color mixing in a printed document for more vibrant colors and bright, but the results would be extremely disappointing when the work comes out of the printer. For starters, the CMY inks depend on the light reflected from the paper to his brilliance, and to mix any color using CMY requires more pigment, which will make the ink more matte or dull. For example, mixing green using RGB green channel only use the most force to mix green mix using CMY cyan and yellow, both near its greatest strength. The CMY subtractive process means we are removing more light with each color is used.

Use RGB colors in printed designs can lead to disaster, the conversion process needs to be handled using profiles. A properly calibrated monitor will minimize errors by showing CMYK colors, and a proper workload profiling will ensure better accuracy when converting an RGB image to CMYK one, and when an image is printed to a printer.