Comment by lloeki
2 years ago
Ambient light will also affect the result.
Not necessarily because the ambient light would affect the screen shows (it's emissive, not reflective) but because the brain also does "auto white/colour balance".
For a fun experiment, get your hand on some heavily yellow-tinted party glasses, go outside on a clear day with a bright blue sky.
When you put them on everything will be stark yellow tinged (and the blue sky will be completely off, like green or pink, can't recall which) but after a little while going on your business, perception adjusts and only a much less dramatic yellowish veil is in effect. You'd look at the sky and see almost-blue.
The kicker is when you remove the glasses: the sky will suddenly be of a glorious pink! (or green, can't recall) Only moments later it'll adjust back to be blue.
A certain wavelength may be absolute blue of a certain kind, but the perceptual system is all relative: "wait, I know this sky should be blue because that's what I've always seen, so let's compensate".
The same kind of effect - although less dramatic - can be achieved with lights that can be adjusted from say 2400K to 6500K and having as reference an object that is known "pure white", like a A4/letter sheet of paper.
This effect, in turn, adjusts how "absolutely displayed" colours are identified by way of biasing the whole perceptive system. AIUI that's the rationale behind Apple's True Tone thingy, aiming to compensate for that.
So the result of this test should be somewhat different depending on ambient lighting temperature.
Digital cameras also do automatic white balance (between yellow and blue) to mimic the automatic white balance of our eye/brain. If cameras didn't do white balance, outdoor photos with sunlight during noon would look extremely blueish, or indoor photos with artificial light would look extremely yellowish.
I like this illustration of how strong our natural white balance is:
https://en.wikipedia.org/wiki/The_dress#/media/File%3AWikipe...
During some heavy dust clouds from nearby wildfires, the sky was a deep and unsettling yellow. However, I couldn’t get a picture of it, because the automatic color balance removed the yellow overcast altogether.
The same problem occurs with photographing the yellow sky when dust from a Sahara sandstorm (presumably coming across the strait of Gibraltar) blows over Europe every few years. But you can set the white balance manually in the camera.
> AIUI that's the rationale behind Apple's True Tone thingy, aiming to compensate for that.
No idea what "AUIU" is, but yes, generally displays should do automatic white balance like iPhones do. I don't know why most Android phones don't seem to do it (pretty sure mine doesn't), and generally TVs/monitors also don't do it. (The required color temperature sensor can't be that expensive?)
> I don't know why most Android phones don't seem to do it (pretty sure mine doesn't), and generally TVs/monitors also don't do it.
The rageguy one would say either patents or "whoa the colors really pop I want that shut up here's my $$$" uncancellable LOOKATMEIAMTHESHINY mall mode, but via Occam'r razor I think mostly because they (manufacturers) simply don't care (about consumers, or about making a good product at all)
TVs/monitors (or laptops even, and more phones that you'd believe) with just a simple auto-brightness are stupendously rare even though Apple does it since forever and a half ago.
Yeah, laptops and TVs not even doing automatic brightness is even more absurd. Though Android phones have automatic brightness since forever, so why do many not have automatic color temperature (white balance)? The color temperature sensor can't be much more expensive than a brightness sensor. It's logically just an RGB brightness sensor.
Android does have a night mode which changes the white balance of the screen at sunset and sunrise, but this is just a binary thing and doesn't respond to actual ambient light.
AIUI as I understand it
Yeah I don't know what that is
3 replies →
Also deliberate software blue light filters. Mine is always on, both on the desktop and on the phone. Many people may forget that they are even using one.
Also my glasses filter blue light.
Fancy way of saying they have a yellow tint (:
3 replies →