You can't believe your eyes: there's no red in this traffic light

Better get this out of the way as soon as possible.

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I have two friends who are color blind. Red and Green are big trouble. Blue is also a problem. It makes me wonder what a color blind person would say about this video, would it have the same effect on them? I will ask them but I won’t be able to before this topic closes :confused:

For the red/green colorblind, this is something that we are well aware of. I’ve worn what I could swear was a green shirt, only to be told that no, it was hot pink. I’ve seen red maple leaves as bright green even though I know they’re red, and brown dry grass as green. In low-visibility conditions, particularly with the old style Edison bulbs, I have had to look really intensely to figure out the stoplight color – and I’ve been convinced it was red only to see it turn yellow. When the world switched to the much brighter and easier to differentiate LEDs driving got a bit less stressful and probably safer. Yay progress.

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If thine eyes offend thee, pluck them out. :man_shrugging:

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The red doesn’t work for me. It comes across as like a black and red plaid sort of pattern.
But the other colors do

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I have red-green colorblindness, though I can mostly see red. Green is basically imaginary for me, though. I can see the reds in these examples.

The brown-orange thing, though, that is a nightmare for me. Without green, a large chunk of stuff is basically orangey, like grass. Traffic lights are white. Brown I can sometimes make out, but it often shades into reds and oranges.

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yeah I’m seeing variation too, I think (among probably many factors) it is highly dependent on screen size. On my laptop it worked for all colors - but on the bigger screen at work the red looks like the Brawny guys shirt - like you say.

That’s “contractual obligation” in a bag.

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I remember it was a real wtf moment when I realized a certain so-called black cat of mine, when seen at just the right angle in full natural sunlight, was actually just really dark red.

I guess same for so-called black pens and markers: nearly all of them are really dark blue or some other color when examined under a microscope.

But now I got me wondering, what about grey cats?

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The effect here is that there is literally no red. The R value is zero on every pixel. Our brain is autocompleting the red that it knows should be there, much like it does with edges, shadows, and other things we’re well-equipped to perceive.

That sounds exactly like what you’re asking for, adding black. You mean a deeper color?

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The grey is a mix of black pigments – melanin, so very dark brown if you care to dilute it like that – and light scattering from the structure of the hairs. :slight_smile:

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Old TVs had a dull grey screen when not in use but in use go even darker.

Light is weird.

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Strawrot berries lose some lusciousness there. Gotta plan ahead for Twi’lek sexy times.

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So, then, we don’t actually need red pixels any more?

A picture of my computer monitor using a photography loupe. The red diodes are lighting up. Any time you have a shade of gray or white that isn’t black (totally black as in an absence of all light) there is a full spectrum of colors in there. Neutral colors are just a more equal balance of those colors. A computer monitor, lcd, or CRT mimic how that works in natural light situations by reproducing it with RGB:



As bcsizemo mentioned (and demonstrated) in an earlier comment, if you turned off the red diodes you’d have an image that looks blue-green and you wouldn’t perceive red.

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But riddle me this (bear with me, really trying for that Pedant Pedant Badge here*): is red a matter of the frequency on the electromagnetic spectrum of light waves reflecting off of an object or is red a matter of the qualia?

I would argue that red only exists in our subjective experience of the color, rather than as a physical phenomenon. If a person sees something and experiences it as red, regardless of the frequency of the light waves, then it is red.

*As is the fashion these days.

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Hardware and software engineer of 30 years experience. No need to mansplain computer monitors to me, thanks.

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Not trying to be a jerk. Sorry. Autopilot honestly no idea who I was replying to. Not here to offend anyone at all.

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You’ll have to pry them from my cold dead red hand!