A screen builds white by adding red, green, and blue light; a printer builds dark by layering cyan, magenta, and yellow ink. RGB and CMYK are two opposite recipes for color — which is why a photo can look different on screen and on paper.
Two ways to make a color
Screens emit light and mix color additively: red, green, and blue light combine, and all three at full strength make white. Printing reflects light and mixes color subtractively: cyan, magenta, yellow, and black (CMYK) inks absorb wavelengths, and more ink means darker. The two systems are near opposites.
Each model can reproduce only a range of colors — its gamut. Vivid screen colors (RGB) sometimes fall outside CMYK's gamut, so a bright design can look duller once printed.
Color 1
Color 2
red + yellow = orange
Mix primaries and watch how combining them shifts the result.
- You combine full red, green, and blue light on a screen.
- Recall what additive mixing of all three produces.
- Contrast that with mixing all inks on paper.
What you should see: All three lights at full make white (additive); piling on all inks approaches black (subtractive) — opposite results from the two models.