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Why we're blind to the color blue

calebkruse.com

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Re: Why we're blind to the color blue

#51

Post by MaxBarraclough »

atishay811 wrote: post #6

This is amazing to see. We should use this for image optimization. When we compress channels, we should compress the blue channel to like 30% while keeping others at fairly large 80% and it might appear better than a 60% compressed image.

As triclops200 says, lossy image compression algorithms have long taken advantage of this. You might be interested in this page, Your Eyes Suck at Blue, which shows an image with the blue channel increasingly compressed:

https://gamesx.com/misctech/visual.htm

edit See also this counterpoint: https://news.ycombinator.com/item?id=573593

Re: Why we're blind to the color blue

#53

Post by SomeHacker44 »

floatrock wrote: post #26
aimor wrote: post #22

I'm tempted to experiment. If I take a blue LED and a green LED in the dark, when I focus on one the other should appear blurred.

Blue LED clocks (like on 'high end' microwaves or appliances) are one of my biggest pet peeve. I'm not an old fart by any stretch -- my eyes are fine -- but the blue blur when looking at the clock at night is a real thing. Fun fact: this phenomenon is similar to why older cars had yellow-tinged fog lights. It's partly light scattering in suspended water droplets (fog), it's partly the perception factors talked about…

Yep, exactly. Scattering of light is proportional to the fourth power of the frequency (or, equivalently, inversely proportional to the fourth power of the wavelength).

I've been telling this to my kids whenever I got the inevitable "why is the sky blue" line. :)

Re: Why we're blind to the color blue

#54

Post by IlliOnato »

What happens in monochrome light, say if you are in a darkroom with a monochrome blue light source, would you be able to focus on objects? Would they appear blurry? Or this "out of focus blue" only happens when other colors are present?

Re: Why we're blind to the color blue

#55

Post by techrat »

crdrost wrote: post #29
crazygringo wrote: post #19

I don't believe the blurred images at the end have anything to do with eye focus, as the author suggests. After all, chromatic aberration is blurring of only a very, very small amount. The demonstrated seemingly negligible perceptual effect of blurring blue to a huge degree in a multicolor image doesn't seem to have anything to do with that, but rather the fact that we perceive primary blue as a much darker color tha…

I'm not sure you're right. At night both I and my wife have reported difficulty reading glowing blue signs compared to glowing red/green signs at the same font size, brightness, and distance. I'm also not sure that the author is correct; the wrong-focal-distance explanation seems rather weak simply because our focal length is adjustable.

You're not alone. I normally have excellent night vision but seeing things in glowing blue, such as the clock on the coffee maker or the microwave, causes the digits to split like double vision and become blurry while everything else remains the same.

Re: Why we're blind to the color blue

#56

Post by techrat »

jbluepolarbear wrote: post #34
crdrost wrote: post #29

Earlier quoted context omitted.

I'm not sure you're right. At night both I and my wife have reported difficulty reading glowing blue signs compared to glowing red/green signs at the same font size, brightness, and distance. I'm also not sure that the author is correct; the wrong-focal-distance explanation seems rather weak simply because our focal length is adjustable.

You have astigmatism. I have a similar issue with blue when not wearing my glasses. I have 20/20 vision, but my astigmatism makes it difficult to focus on certain things. A computer being a big one. Blue light blockers help, but with proper astigmatism correction I don’t need them.

20/10 vision in one eye, 20/13 in another, no astigmatism.

Blue LEDs in clocks when viewed at night look completely fucked up.

Re: Why we're blind to the color blue

#57

Post by pier25 »

drcongo wrote: post #50

One of my favourite series in art is Yves Klein's blue work. For anyone unfamiliar, he found a blue that he considered the bluest possible blue [1], and went on a journey painting everything in that blue. I loved that he did this, and then eventually managed to get to an exhibition of his work at the Tate Modern and was absolutely blown away by it - it really needs to be seen in the flesh to appreciate it. There's so…

Great anecdote!

Reminded me of the short story Zima Blue by Alastair Reynolds (which was adapted into an animation short on Netlifx's "Love, Death and Robots").

Re: Why we're blind to the color blue

#58

Post by glial »

inglor_cz wrote: post #8

Interestingly, many ancient text sources do not speak of blue color at all, using other expressions. https://en.wikipedia.org/wiki/Wine-dark_sea_(Homer)

There's a fascinating Radiolab episode that expands on this topic, asking the question about whether 'blue' is a feature of nature or a cultural invention & transmission:

https://www.wnycstudios.org/podcasts/radiolab/segments/21121...

Re: Why we're blind to the color blue

#59

Post by selestify »

drcongo wrote: post #50

One of my favourite series in art is Yves Klein's blue work. For anyone unfamiliar, he found a blue that he considered the bluest possible blue [1], and went on a journey painting everything in that blue. I loved that he did this, and then eventually managed to get to an exhibition of his work at the Tate Modern and was absolutely blown away by it - it really needs to be seen in the flesh to appreciate it. There's so…

As someone who hasn't seen it in the flesh yet, and doesn't "get" modern art unless someone explicitly spells it out for me, could you elaborate more on why it's so spectacular?

For example, Blue Monochrome [1] seems to my uneducated eye to be just a layer of pure blue that every wall painter recreates every time they paint a wall blue. Why is the Blue Monochrome piece more than just a wall painted blue?

[1] https://www.moma.org/collection/works/80103

Re: Why we're blind to the color blue

#60

Post by thehappypm »

crazygringo wrote: post #19

I don't believe the blurred images at the end have anything to do with eye focus, as the author suggests. After all, chromatic aberration is blurring of only a very, very small amount. The demonstrated seemingly negligible perceptual effect of blurring blue to a huge degree in a multicolor image doesn't seem to have anything to do with that, but rather the fact that we perceive primary blue as a much darker color tha…

I'm sure you could find an image where blurring blue ruins it, and blurring red and green have no impact. This feels like cherrypicking especially given how trivial it would be to just show a bunch of examples.
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