What is RBG Color?
RGB is called "the three primary colors of additive color mixing of light" and is a method of emitting and displaying light on displays and other devices.
It is composed of three light sources, Red, Green, and Blue, and when these three lights are superimposed, the color becomes white.
The more colors are mixed, the whiter the color becomes (the brighter the color), and this is also called the "additive method.
What is CMYK Color?
CMYK is mainly used for printing and color printers. Basically, it is composed of three colors, Cyan, Magenta, and Yellow, and when mixed, the color becomes black. In reality, however, black is not a true black, so K (Black) is added.
The more colors are mixed, the darker the color becomes (lower brightness), which is called "color reduction.
The more colors are layered, the darker (blacker) the color becomes.
Difference in reproducibility
The major difference between RGB and CMYK is that the color gamuts that can be expressed are different because the methods of expression are fundamentally different. RGB has a wider color gamut, while CMYK cannot reproduce some of the colors that RGB can.
Therefore, RGB colors cannot be used as they are in printing.
It is the same meaning as fluorescent colors cannot be reproduced with paints.
A photo image taken with a digital camera can express vivid colors on a display, but when converted to CMYK for printing, the colors in the RGB color gamut are replaced by the closest color that CMYK can express, and as a result, the vivid colors that can only be expressed in RGB may become dull.