RGB adopts additive method, that is, RGB can produce gray white when added in an equal amount. The more colors are added, the brighterit is, it belongs to three primary colors of color and light, which are usually used on display, scanner, and other equipment; CMYK is subtractive method, that is, the deeper it can be added in equal amount, it belongs to CMY, which are generally used in four-color printing.RGB color gamut is larger and CMYK color gamut is smaller, so some colors in RGB cannot be represented in CMYK.

The printing adopts CMY + K four color mixture overprint, so when designing the manuscript, you must first set the color mode as CMYK, and the color value used in the file as CMYK to achieve the printing color consistency. If the manuscript uses RGB, you can only select the closest color when converting to CMYK printing, which will result in a large color difference in the finished product.