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Stop Colour Theory

partone.github.io

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Re: Stop Colour Theory

#31

Post by pmiller2 »

I do want to seriously address one of the points on this page. Water is, in fact, blue. It sometimes appears green because of algae and other organisms in it. Here is a better explanation than I could have come up with:

> The water is in fact not colorless; even pure water is not colorless, but has a slight blue tint to it, best seen when looking through a long column of water. The blueness in water is not caused by the scattering of light, which is responsible for the sky being blue. Rather, water blueness comes from the water molecules absorbing the red end of the spectrum of visible light. To be even more detailed, the absorption of light in water is due to the way the atoms vibrate and absorb different wavelengths of light. [0]

Likewise, while nitrogen is colorless, oxygen is actually blue as well, which, in turn, means that air is actually slightly blue (this is not the cause of the blue sky -- see [1]).

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[0]: https://www.usgs.gov/special-topic/water-science-school/scie...

[1]: https://en.wikipedia.org/wiki/Rayleigh_scattering

Re: Stop Colour Theory

#33

Post by oraknabo »

scottlawson wrote: post #20

> Furthermore, organisations such as the International Commission on Illumination have made it their goal to keep Colour Theory at the forefront of colour science. The illuminati!

How did I read that sentence and 1) not question whether this was a real organization and 2) not catch that reference?

Big thanks for pointing this out.

Re: Stop Colour Theory

#34

Post by jabirali »

dathinab wrote: post #26
georgeecollins wrote: post #16

Earlier quoted context omitted.

Right, you say additive and subtractive, I think of it as emmissive colors vs reflective colors. That point seems to get ignored. Some of this is interesting-- like every color is a frequency. But human vision systems are probably not innately tuned to perceive every frequency along a chunk of spectrum with an equal weight. Training and cognition probably influence our acuity in certain parts of the range.

It's not just cognition but physical limitations of our eye. Through the effect of cognition and training are wastly underestimated in my experience, like look into what the color brown is.

Precisely. That’s also why our screens use RGB emittors: that’s the frequencies our eyes have sensors for.

Pictures shown on a human screen must look really weird for a species with different color vision than us...

Re: Stop Colour Theory

#35

Post by fmajid »

traverseda wrote: post #28
georgeecollins wrote: post #16

Earlier quoted context omitted.

Right, you say additive and subtractive, I think of it as emmissive colors vs reflective colors. That point seems to get ignored. Some of this is interesting-- like every color is a frequency. But human vision systems are probably not innately tuned to perceive every frequency along a chunk of spectrum with an equal weight. Training and cognition probably influence our acuity in certain parts of the range.

> like every color is a frequency Hot pink isn't a frequency. It does not appear in the visible light spectrum. You can only produce it by combining multiple "impure" frequencies. You generally produce it by combining a spike of low-frequency red with a spike of high-frequency violet. Human eyes try to "triangulate" a complex spectral analysis into an absolute position in a colour space, that colour space is the surf…

A sub-manifold of the Real Projective Plane RP2
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