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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

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 4y 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 4y 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 4y 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.

neltnerb 4y 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 4y 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 4y 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.