Im always confused by RGB. I learned that if you want orange, you mix red and yellow. If you want green, you mix blue and yellow, if you want purple, you mix red and blue.

How is it that computers need green and not yellow?

  • randombullet@lemmy.world
    link
    fedilink
    English
    arrow-up
    33
    ·
    1 year ago

    It’s just the concept of additive color mixing vs subtractive color mixing.

    Adding pigments together will ultimately create black. While adding more light together will ultimately make white.

    With pigments you’re taking away from the color space. You paint red to subdue all other colors except for red.

    But you use red light to make sure red is better seen.

    • NameOfWhimsy@reddthat.com
      link
      fedilink
      English
      arrow-up
      14
      ·
      1 year ago

      It’s kinda cool (to me at least lol) how literal the terms “additive” and “subtractive” for color mixing are. With additive mixing (such as on a computer screen), you start with black and add the primary colors (RGB) in different combinations. If you add all of them you get white.

      Subtractive mixing (like pigments) starts from white and “subtracts” those same RGB colors. You can think of cyan, magenta, and yellow as “minus red”, “minus green”, and “minus blue” respectively, since that’s which wavelengths thise pigments absorb. So mixing cyan and magenta for instance gives you “white (RGB) minus red minus green”, which leaves only blue.