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I dont think this is true. direct sunlight can be many shades of white. It differs in the morning and the evening and it is mostly yellow. The yellowness of th

I dont think this is true. direct sunlight can be many shades of white. It differs in the morning and the evening and it is mostly yellow. The yellowness of the sunshine is a direct result of raleigh scattering and other atmospheric effects.the blue part of the spectrum that comes from the sun is scattered by the sky, making the sky blue. Taking away the blue makes the nonscattered sunlight yellowish. On photos of the moon, you see the true color of sunlight. Which is a pure white.

bnegreve 5y ago
Of course there are different shades of white, what I am saying is that the color of the sun during the day is what people most would classify as "white" and not as "yellow" if it the color was printed on a sheet of paper. If the sun color was actually yellow, people wouldn't be able to tell the difference between a white object and yellow object under the sun light (they would both appear yellow). And clearly they are. On the other hand a white object doesn't get any "whiter" under another kind of light than it appears under direct sun light, this again is because the sun light is white, and not yellow. Of course there is some subjectivity here, but it is a misconception to call the sun light yellow. For example, this "bright sun" RGB [1] color, is clearly not the color of direct sun light. Hopefully, you will agree with this. [1] https://www.colorcombos.com/colors/FCD440 https://www.colorcombos.com/colors/FCD440
- nine_k 5y ago
  Sunlight is wide-band (see "black body spectrum"). This is why a white object (that reflects all light equally) and a yellow object (which mostly reflects reds and greens) are discernible under such light, even under sunset light which is visibly yellow or orange. The sunset orange light still contains many other colors. A yellow object and a white object would be not discernible under a very narrow-band yellow light, or a mix of two narrow-band red and green lights of right proportions. This is how LEDs and lasers emit light, but totally unlike hot objects (like Sun) or fluorescent lamps (like "natural light" LED lamps) emit light.
  - bnegreve 5y ago
    Look, my point is simple: if you agree that snow and sugar are white, then the sunlight is also white. It has to be because white was historically described as the color of the snow (or whatever is white) under the sunlight. Now, if you want to adopt a more precise definition of white and other colors, based on (not so) recent scientific insights about the light, you can. Then the sunlight is not white, neither is snow or sugar. And is also certainly not yellow. Let's be honest, the sun light is almost perfectly white, and kids use yellow to draw the sun, because it wouldn't make sense to draw it with white.
gmueckl 5y ago
The fundamental yellowness of sunlight is not Rayleigh scattering, but the sun's natural black body spectrum. See my reply to the sibling comment.
- nine_k 5y ago
  There is another catch. Sun's surface is about 6000K. A light with such color temperature would be considered bluish by most people if they looked directly at a lamp with such a spectrum. Rayleigh scattering lowers it to 5600-5800K at noon time, but still most humans would call a moderately bright lamp of this color "bluish". The eye has a built-in white balance correction, and it moves the white point towards longer waves as the brightness lowers. This is why a single 5600K lamp in a room makes bluish light, while 10 of the same lamps make it lit by bright white. Same, a single 2500K lamp in a room makes a calming sort-of-white light. but 10 such lamps make a unmistakably yellow light. The sunlight outside at a cloudless summer noon is very bright (one usually even wants to wear sunglasses), so the sun looks white or yellowish, especially in contrast to the blue sky.

bnegreve 5y ago

Of course there are different shades of white, what I am saying is that the color of the sun during the day is what people most would classify as "white" and not as "yellow" if it the color was printed on a sheet of paper. If the sun color was actually yellow, people wouldn't be able to tell the difference between a white object and yellow object under the sun light (they would both appear yellow). And clearly they are. On the other hand a white object doesn't get any "whiter" under another kind of light than it appears under direct sun light, this again is because the sun light is white, and not yellow. Of course there is some subjectivity here, but it is a misconception to call the sun light yellow. For example, this "bright sun" RGB [1] color, is clearly not the color of direct sun light. Hopefully, you will agree with this. [1] https://www.colorcombos.com/colors/FCD440 https://www.colorcombos.com/colors/FCD440

nine_k 5y ago
Sunlight is wide-band (see "black body spectrum"). This is why a white object (that reflects all light equally) and a yellow object (which mostly reflects reds and greens) are discernible under such light, even under sunset light which is visibly yellow or orange. The sunset orange light still contains many other colors. A yellow object and a white object would be not discernible under a very narrow-band yellow light, or a mix of two narrow-band red and green lights of right proportions. This is how LEDs and lasers emit light, but totally unlike hot objects (like Sun) or fluorescent lamps (like "natural light" LED lamps) emit light.
- bnegreve 5y ago
  Look, my point is simple: if you agree that snow and sugar are white, then the sunlight is also white. It has to be because white was historically described as the color of the snow (or whatever is white) under the sunlight. Now, if you want to adopt a more precise definition of white and other colors, based on (not so) recent scientific insights about the light, you can. Then the sunlight is not white, neither is snow or sugar. And is also certainly not yellow. Let's be honest, the sun light is almost perfectly white, and kids use yellow to draw the sun, because it wouldn't make sense to draw it with white.

gmueckl 5y ago

The fundamental yellowness of sunlight is not Rayleigh scattering, but the sun's natural black body spectrum. See my reply to the sibling comment.

nine_k 5y ago
There is another catch. Sun's surface is about 6000K. A light with such color temperature would be considered bluish by most people if they looked directly at a lamp with such a spectrum. Rayleigh scattering lowers it to 5600-5800K at noon time, but still most humans would call a moderately bright lamp of this color "bluish". The eye has a built-in white balance correction, and it moves the white point towards longer waves as the brightness lowers. This is why a single 5600K lamp in a room makes bluish light, while 10 of the same lamps make it lit by bright white. Same, a single 2500K lamp in a room makes a calming sort-of-white light. but 10 such lamps make a unmistakably yellow light. The sunlight outside at a cloudless summer noon is very bright (one usually even wants to wear sunglasses), so the sun looks white or yellowish, especially in contrast to the blue sky.