Timeline for How much red, blue, and green does white light have?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Nov 17, 2014 at 18:17 | comment | added | David Hammen | +1. Sunlight is white when the Sun is not near the horizon. It's not a good idea, but you can briefly look at the Sun briefly when it is near the horizon. You will see a reddish or yellowish Sun at such low elevations. You can't look at the Sun once it has climbed into the sky. Reflexes force you look away. You would see a brilliant white ball (not red, not yellow, just white) if you could look at the Sun when it is high in the sky. | |
| Jul 31, 2014 at 12:47 | comment | added | rob♦ | @slebetman Some sunny day, use a pinhole camera to make an image of the sun's disk. (If you feel extra-motivated, use a flat mirror to send the sunlight horizontally about 50 feet into a dark alcove or interior wall, and use a pencil-sized pinhole to get enough detail to see sunspots on a six- to eight-inch image.) Put your image on a white backdrop. I dare you to call that color yellow! Sunlight is white. | |
| Jul 31, 2014 at 4:17 | comment | added | slebetman | I have always considered sunlight to be slightly yellowish and I think a lot of people here feel the same. I guess we grew up with CFL light which changed our concept of "white". | |
| Jul 30, 2014 at 15:25 | comment | added | gerrit | Note that blue light is preferentially scattered away from the sunlight reaching the Earth, so the colour of the direct sunlight we seeing from Earth is not the colour we would see from space. | |
| Jul 30, 2014 at 14:27 | comment | added | Jon Custer | And at the store you can buy bulbs with different equivalent black body temperatures - they will look different (particularly to different people), but they are still "white". Human perception is more than just the response of the color receptor - there is a lot of processing as well going on, and it accepts a fairly broad range of "white". | |
| Jul 30, 2014 at 14:14 | history | answered | rob♦ | CC BY-SA 3.0 |