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What's the best way to learn color theory? Like actually, properly learn it? I consider my interest in TV/Movies to cross over into the enthusiast category, and

What's the best way to learn color theory? Like actually, properly learn it? I consider my interest in TV/Movies to cross over into the enthusiast category, and I work with medical images and video (compression mostly). I've spent time with the basics, and have recently started reading about BT 709 etc., but am unsure how best to really dive-in to color theory headfirst

PaulHoule 5y ago
If you give up your RGB sliders for HSV sliders you’ve taken a big step. Value (bright vs dark) is more important than anything else. If you were picking foreground and background colors for text whether or not it is readable depends on the difference in values, not the hues. Any image should be meaningful if seen in black and white, not just for color blind individuals but for normal sighted individuals too. The Ansel Adams zone system is good for thinking about this, even for non-photographic images. He identifies 11 major bands of value which are about as many shades as you are going to get in a bad print or viewing environment, say with a thermal printer or newsprint. In a top quality print and viewing environment however each of those zones except the most extreme is able to show meaningful detail. Of course an image can choose to not use certain zones but generically I’d say the ideal image looks good under bad circumstances but under good circumstances it has something to delight the eye in all the zones. (Reference art from Pokémon often has well-thought out uses of value because it has to play across various media.)
BlueTemplar 5y ago
This is the best free resource that I'm aware of : http://www.handprint.com/LS/CVS/color.html http://www.handprint.com/LS/CVS/color.html
neltnerb 5y ago
I think a huge first step for me didn't require any textbooks, but simply manually calculating the CIE coordinates based on the actual light spectrum. There are some really good articles online at this point, but I think everyone should probably just do this once. The wikipedia articles on colorspace are pretty darn good, albeit spread over way too many pages... I feel like if you can do that math you understand a ton. Including why red and blue mixed is purple =) The integrals you need are at the bottom. https://en.wikipedia.org/wiki/CIE_1931_color_space https://en.wikipedia.org/wiki/CIE_1931_color_space
- neltnerb 5y ago
  Two other super helpful mental experiments -- - Why is there a "white locus"? How much does my hue shift under different color temperatures (ignoring CRI, which I suggest you do for now) - With what math can I reproduce a color using three other colors in combination?
  - bick_nyers 5y ago
    The other commenters shared some seriously great stuff, but as a Math major, you have my personal thanks for informing me that there were integrals I could solve.
    - neltnerb 5y ago
      Fair, coming from a physics/chemistry/biology background seeing the connection between the spectrum of light being seen and the color you convert it to was really enlightening. I knew it had to do with phosphors, but the science is fairly understandable. The chemicals that pick up light respond to different wavelengths differently. However, if they get excited, they are a [1] (as far as I think we understand). So a single phosphor can't tell anything about the wavelength other than a probability distribution. Then you take three probability distributions and identify a single unique color in our heads for it. And that's why every color-space ultimately has three parameters, it's all just different projections and mappings but physically there's really just a spatially isolated signal that tells you which of three phosphors were hit and how much, and then a ratio to downsample it to a perceptual color. And then you look at the overlap and see how for wavelengths you see as blue, the "blue" phosphor is only about as active as the "green" phosphor (which are confusing misnomers anyway) but your brain sees both being active equally as "blue". And then that "red" secondary hump gets hit when the wavelength moves from blue towards violet -- activating the "red" phosphor and making vision into a wheel. It was always one of those "this is obvious until I think about it" moments when I wondered why 400nm and 700nm aren't ends of a spectrum in our vision rather than a wheel, there's no obvious theoretical reason for it I think. It's just a possibly pure coincidence of that "red" phosphor having a second hump. It's nice to do the conversion for real a few times with example colors or black body radiation. Seeing how this works a little closely makes a bunch of stuff like imaginary colors make sense biologically with saturating certain phosphors.

PaulHoule 5y ago

If you give up your RGB sliders for HSV sliders you’ve taken a big step. Value (bright vs dark) is more important than anything else. If you were picking foreground and background colors for text whether or not it is readable depends on the difference in values, not the hues. Any image should be meaningful if seen in black and white, not just for color blind individuals but for normal sighted individuals too. The Ansel Adams zone system is good for thinking about this, even for non-photographic images. He identifies 11 major bands of value which are about as many shades as you are going to get in a bad print or viewing environment, say with a thermal printer or newsprint. In a top quality print and viewing environment however each of those zones except the most extreme is able to show meaningful detail. Of course an image can choose to not use certain zones but generically I’d say the ideal image looks good under bad circumstances but under good circumstances it has something to delight the eye in all the zones. (Reference art from Pokémon often has well-thought out uses of value because it has to play across various media.)

BlueTemplar 5y ago

This is the best free resource that I'm aware of : http://www.handprint.com/LS/CVS/color.html http://www.handprint.com/LS/CVS/color.html

neltnerb 5y ago

I think a huge first step for me didn't require any textbooks, but simply manually calculating the CIE coordinates based on the actual light spectrum. There are some really good articles online at this point, but I think everyone should probably just do this once. The wikipedia articles on colorspace are pretty darn good, albeit spread over way too many pages... I feel like if you can do that math you understand a ton. Including why red and blue mixed is purple =) The integrals you need are at the bottom. https://en.wikipedia.org/wiki/CIE_1931_color_space https://en.wikipedia.org/wiki/CIE_1931_color_space

neltnerb 5y ago
Two other super helpful mental experiments -- - Why is there a "white locus"? How much does my hue shift under different color temperatures (ignoring CRI, which I suggest you do for now) - With what math can I reproduce a color using three other colors in combination?
- bick_nyers 5y ago
  The other commenters shared some seriously great stuff, but as a Math major, you have my personal thanks for informing me that there were integrals I could solve.
  - neltnerb 5y ago
    Fair, coming from a physics/chemistry/biology background seeing the connection between the spectrum of light being seen and the color you convert it to was really enlightening. I knew it had to do with phosphors, but the science is fairly understandable. The chemicals that pick up light respond to different wavelengths differently. However, if they get excited, they are a [1] (as far as I think we understand). So a single phosphor can't tell anything about the wavelength other than a probability distribution. Then you take three probability distributions and identify a single unique color in our heads for it. And that's why every color-space ultimately has three parameters, it's all just different projections and mappings but physically there's really just a spatially isolated signal that tells you which of three phosphors were hit and how much, and then a ratio to downsample it to a perceptual color. And then you look at the overlap and see how for wavelengths you see as blue, the "blue" phosphor is only about as active as the "green" phosphor (which are confusing misnomers anyway) but your brain sees both being active equally as "blue". And then that "red" secondary hump gets hit when the wavelength moves from blue towards violet -- activating the "red" phosphor and making vision into a wheel. It was always one of those "this is obvious until I think about it" moments when I wondered why 400nm and 700nm aren't ends of a spectrum in our vision rather than a wheel, there's no obvious theoretical reason for it I think. It's just a possibly pure coincidence of that "red" phosphor having a second hump. It's nice to do the conversion for real a few times with example colors or black body radiation. Seeing how this works a little closely makes a bunch of stuff like imaginary colors make sense biologically with saturating certain phosphors.