Timeline for How much red, blue, and green does white light have?
Current License: CC BY-SA 4.0
14 events
| when toggle format | what | by | license | comment | |
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| May 25, 2018 at 21:32 | history | edited | Nat | CC BY-SA 4.0 |
deleted 51 characters in body
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| Aug 1, 2014 at 13:01 | comment | added | Code Jockey | decent answer, but what about tetrachromes? | |
| Aug 1, 2014 at 4:57 | comment | added | hobbs | If you're mathematical: take the curve that represents the spectrum of the light source, and multiply it at each wavelength with the curve that represents the sensitivity of a given kind of cone, then take the integral under the product curve. Repeat for each cone type, and you have the LMS tristimulus values. Two sources that give the same LMS will appear the same. The curves (spectra) don't have to be the same, just the integrals that come out of them. | |
| Jul 31, 2014 at 10:34 | vote | accept | Black Dagger | ||
| Jul 31, 2014 at 4:12 | comment | added | slebetman | White, gray and black are actually the same color. Just like bright red, red and dark red are "reds". Gray is just dark white and black is very dark white. You're just changing the luminosity. Not the hue or even saturation. | |
| Jul 30, 2014 at 21:11 | comment | added | Bobson | @DavidHammen - I love that one. When you put your finger over 90% of the center, and then shift it slightly so that it covers the whole center and then not, you can almost watch your eyes reevaluating the colors in regards to each other. Or at least I can... | |
| Jul 30, 2014 at 18:47 | comment | added | David Hammen | @EmilioPisanty - Here's another optical illusion of the same ilk. | |
| Jul 30, 2014 at 18:01 | comment | added | Emilio Pisanty | This is the basis of this classical optical illusion. Perceived colour is (strongly) context-dependent. | |
| Jul 30, 2014 at 17:31 | comment | added | David Hammen | @BlackDagger - Our eyes aren't spectrometers. There's only so much our eyes can do with but three kinds of color receptors. Look at the image you posted. That's anything but a white noise spectrum. You see that light as white because it excites each of those three kinds of receptors similarly to how light with a much flatter spectrum would excite them. There's also a lot of signal processing going on in your eyes and brain. Your nice summertime white clothes look white at noon and at sunset, but point a spectrometer at them and you'll see rather different spectra. | |
| Jul 30, 2014 at 16:03 | comment | added | Black Dagger | @David Hammen You mean to say that our eyes are insensitive to a range of light-combinations that it identifies all the combinations as white? | |
| Jul 30, 2014 at 15:49 | comment | added | BowlOfRed | @gerrit, that would depend on many things. The human visual system does not create a static mapping between a particular spectrum and a single perceived color. Instead as lighting conditions and spectra change, our visual system re-evaluates and changes perception. It allows us to see "white" things in broad daylight as well as evening twilight. As such, a "flat" spectrum would be interpreted depending on what else was seen close to it in time and space. There is no context-independent answer. | |
| Jul 30, 2014 at 15:42 | comment | added | Antonio Ragagnin | @gerrit, I guess gray | |
| Jul 30, 2014 at 15:26 | comment | added | gerrit | Suppose the light is spectrally flat — what colour would we perceive? | |
| Jul 30, 2014 at 14:55 | history | answered | David Hammen | CC BY-SA 3.0 |
