

paint and light are different. for light, you are adding colours onto black to make it brighter; for paint, you are subtracting colours from white to make it darker. thus, respectively, additive and subtractive colours.
red, yellow, and blue being “primary colours” is there because people probably think “magenta” and “cyan” are too complex of concepts to teach young kids. it is cool to have a way to make orange and purple without delving into paint ratios, though. it’s good enough for general use for sure, but if you want to get into colour accuracy for print, CMY is the way to go.
here’s a quick and simple cheat sheet to help you out!
additive colours (RGB; screen pixels, LEDs):
- nothing = black
- red + green = yellow
- green + blue = cyan
- blue + red = magenta
- red + green + blue = white
subtractive colours (CMY(K); paint, prints, colouring pencils):
- nothing = white
- cyan + magenta = blue
- magenta + yellow = red
- yellow + cyan = green
- cyan + magenta + yellow = black



adam ragusea’s videos have taught me so much about cooking. he’s very much an advocate for cooking by feel, he teaches a lot of the food science behind his recipes, and his recipes are very easy to follow.