Where to Find the Colors Your Screen Can't Show You(moultano.wordpress.com) |
Where to Find the Colors Your Screen Can't Show You(moultano.wordpress.com) |
> Nearly every species of scorpion intensely fluoresces under UV light. […] Scorpions have photoreceptors in their tails, separate from their eyes. […] It is hypothesized that a scorpion uses this fluorescence to tell whether any bit of its body is left exposed from its hiding place. Its tail “looks” down at its body, and if it sees its own fluorescence, it knows it is exposed to light, and in danger.
And a special call-out to the “Andean Cock-on-a-Rock” :), see a photo in the article.
In reality, the greatest defect of the sRGB color space, which is still too frequently the default color space, is that it is not able to reproduce many saturated orange/red/purple colors, which are very frequently encountered around us, e.g. in flowers, fruits and clothes.
The missing orange-red-purple corner appears small in the diagram in comparison with the missing blue-green corner, but in reality humans perceive much more different colors in the orange/red/purple corner, so the relation between those areas would be opposite in a uniform color space.
The Display P3 color space is much better than sRGB for reproducing orange/red/purple colors and now it is available even in many cheap monitors. However many monitors that can reproduce Display P3 come configured by default to use just sRGB. Such monitors should always be reconfigured to use Display P3.
Monitors that can reproduce an even greater part of the Rec. 2020 color space are obviously better than those that can do only Display P3, but such monitors with a higher color gamut are usually more expensive. The full Rec. 2020 color space can be reproduced only with laser projectors, because it uses monochromatic primary colors.
If I understand correctly fig. 3 in [1] should be perceptually uniform. The bluegreens missing from sRGB, but present in BT.2020 comprise a sizeable chunk.
[1] https://www.researchgate.net/publication/345252499_Evaluatin...
This post is making me feel a bit inspired to go outside and immerse myself in the forest to take in the greens. Thanks for sharing.
The most striking experience I had was working with a blue laser (430nm). The best way I found to describe its color is that it was screaming "blue" at me. Since then, I'm always disappointed when looking at a screen displaying #0000FF.
Thanks for such a beautiful article about not looking at a screen: I'm off outside... :)
I do have a question that the article doesn't seem to attempt to answer, though. The article says (paraphrased in my new understanding) that any spectra which makes the cones in your eyes react the same way will result in seeing the same colour. Do we know of any examples of this?
(Colour-blindness seems like an obvious example; I'm curious though if there are any examples of two common scenarios where it can be demonstrated that there are different spectra in each, and yet most people will see them as the same colour.)
See the first minutes of this video, where he has a spectrum analyser: https://youtu.be/-DyrBDsKA5s?si=mRJPT2ecy6NqpB4N
On one side you have an apple, illuminated by natural sunlight. it fills your eye with a rich texture of subtly mixed frequency's covering the whole gamut of visible and invisible light. On the other a picture of an apple composed of brutal pure frequencies only emitting at 430, 540, 570 Nm. Can you tell the difference?
Modern color modeling is much richer then 3 parameters, because human vision is much more complex than simply color frequencies. CIE 1931 was low brightness, 2 degree field of vision, center of vision derived. As brightness increases, color perception shifts. Colors are NOT linear; sRGB and CIE 1931 chose such a small section of human vision that they approximate that section with a linear assumption. Modern CIECAM models are not linear, are not 3 parameter, because color is not linear (CIECAM02 is 6 parameter [2], there are several after that one). A century of experiments, wide color gamuts, HDR, have thrown out CIE 1931 as a good model. It’s only momentum now, and slowly higher end things are replacing it.
A good introduction is Color Appearance Models, by Mark Fairchild, also any of his technical papers give a starting point into the science.
[1] https://community.acescentral.com/t/cie-2015-cmfs-what-would...
Either way, you can project a volume onto a plane, which is great for communicating visual data on paper or screen.
The interesting question is "why that arc in particular"; my ignorance will shine through if I speculate.
I assume that the projection encodes something about our relative perception of each cone's band, hence the big green corner.
This will actually differ from person to person. If you look at a pure yellow wavelength light next to a red/green light mixed such that they create the exact same perceived yellow to you, it will look different to another person.
Aside from that, not really sure what a 3d view with the dimensions being r,g,b would actually offer