Why we're blind to the color blue • Hacker News Board

Re: Why we're blind to the color blue

#191

Post by dalmo3 » Sat, Jul 17, 2021, 6:48 AM UTC

sgtnoodle wrote: post #174

glenngillen wrote: post #168

Earlier quoted context omitted.

I’ve found my people! I have similar issues and nobody I’ve ever spoken to about it seems to have the same experience. Two similar issues I’ve had, and I’ve wondered if they’re related, are: - at conferences with very large overhead projection sometimes the setup produces an effect where each time I blink it’s like it separates the RGB elements. It’s like a combination of being able to see the refresh rate (like when…

That's most certainly the display sequentially flashing red, green and blue sequentially in time to approximate shades and hues. When you stare right at it, your eye averages the photons with a time constant of 1/30th of a second or so, and so you don't perceive the flicker. When you move your eye or blink, though, individual portions of your eye are exposed to only relatively narrow time slices, and so re only expos…

Thanks for the explanation!

I can certainly perceive all those flickering effects when moving the eyes. Slow PWM is hell, but some stuff like colour separation can be cool too.

My favourite trick is making a digital clock's numbers "slide" over the clock's surface, in a sort of parallax way. I guess that's due to low refresh rates, so for a very brief moment there's a disconnect between the clock's physical position and the last know position of the digits.

Re: Why we're blind to the color blue

#192

Post by madaxe_again » Sat, Jul 17, 2021, 6:52 AM UTC

madaxe_again wrote: post #2

I’ve always found blue LED or cold cathode signs absolutely illegible at night - just an amorphous blur. I always thought it was just me.

This was offensive? Seriously? Christ, you lot are weird.

Re: Why we're blind to the color blue

#193

Post by CamperBob2 » Sat, Jul 17, 2021, 8:18 AM UTC

sgtnoodle wrote: post #133

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 dunno, but when I look at glowing blue signs and blue Christmas lights at night, they look significantly more fuzzy than other color lights.

It's true that we don't focus well on blue light sources, but it's also true that this web page does not demonstrate that fact in the slightest.

Re: Why we're blind to the color blue

#194

Post by parm22 » Sat, Jul 17, 2021, 9:12 AM UTC

The Himba tribe of Namibia cannot see the color blue (same tribe that Nike studied about running long distances). They are an isolated tribe that can't see blue ... The study included presenting a chart with 10 boxes where 9 boxes were green and 1 was blue but all boxes had the same hue (reasonable value that we can easily differentiate); and the entire village couldn't identify 'the one box that was different from the others'. They relocated an orphan newborn to another tribe and the child easily identified the color blue proving it wasn't genetic. It's weird how all the videos about it have been deleted. It was presented on a TED Talk and an unrelated National Geographic episode. A linguist on TED Talks did a whole talk on how vocabulary defines what we see. I wonder if this was a correction and hence, the removal.

Re: Why we're blind to the color blue

#195

Post by stOneskull » Sat, Jul 17, 2021, 9:24 AM UTC

salawat wrote: post #169

Talanes wrote: post #155

Earlier quoted context omitted.

Shoe size is an inherent byproduct of having feet of a certain dimension. A prescription has to be prescribed. If we're doing dumb analogies, it's like you're trying to insist a homeless man must have an address.

...Actually, that's a real problem in the financial services sector. You can't satisfy KYC requirements without an address of record. Off topic, but I'm jumping around a bit tonight.

i'm imagining a homeless man receiving his begging money via a bitcoin QR code on his phone.. i hope he has a bitcoin atm nearby.

Re: Why we're blind to the color blue

#196

Post by stOneskull » Sat, Jul 17, 2021, 9:29 AM UTC

jbluepolarbear wrote: post #186

georgeburdell wrote: post #184

Earlier quoted context omitted.

Astigmatism is easy to self-detect, and it's quite different from the light focusing to the wrong plane. Astigmatism will noticeably warp the entire shape of the distant point object, rather than just make it "fuzzy" in an isotropic manner.

Source? Astigmatism can blur and distort. https://patient.info/eye-care/astigmatism

for me, it's mainly the difference in looking up and down compared to looking left and right.

Re: Why we're blind to the color blue

#197

Post by zokier » Sat, Jul 17, 2021, 9:30 AM UTC

chmaynard wrote: post #135

seanalltogether wrote: post #78

I'm surprised the author doesn't mention the fact that only 2%-5% of the cone cells in our eyes can perceive blue. That's a huge factor in how well we process colors with blue light.

Citation please.

Not exactly the same thing, but we have practically no blue receptors in our foveas:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2715890/

Re: Why we're blind to the color blue

#198

Post by parm22 » Sat, Jul 17, 2021, 9:34 AM UTC

parm22 wrote: post #194

The Himba tribe of Namibia cannot see the color blue (same tribe that Nike studied about running long distances). They are an isolated tribe that can't see blue ... The study included presenting a chart with 10 boxes where 9 boxes were green and 1 was blue but all boxes had the same hue (reasonable value that we can easily differentiate); and the entire village couldn't identify 'the one box that was different from t…

I guess this is the updated understanding: https://www.youtube.com/watch?v=mgxyfqHRPoE

They cant see the color blue and we cant see hue in green

Re: Why we're blind to the color blue

#199

Post by sgtnoodle » Sat, Jul 17, 2021, 10:05 AM UTC

dalmo3 wrote: post #191

sgtnoodle wrote: post #174

Earlier quoted context omitted.

That's most certainly the display sequentially flashing red, green and blue sequentially in time to approximate shades and hues. When you stare right at it, your eye averages the photons with a time constant of 1/30th of a second or so, and so you don't perceive the flicker. When you move your eye or blink, though, individual portions of your eye are exposed to only relatively narrow time slices, and so re only expos…

Thanks for the explanation! I can certainly perceive all those flickering effects when moving the eyes. Slow PWM is hell, but some stuff like colour separation can be cool too. My favourite trick is making a digital clock's numbers "slide" over the clock's surface, in a sort of parallax way. I guess that's due to low refresh rates, so for a very brief moment there's a disconnect between the clock's physical position…

I totally know that digital clock effect you're talking about. It's caused by something else though. It's actually a physiological hallucination due to high power ultrasonic waves coming out of those types of clocks. Rather than smoothly turning a small crank at 60rpm like in an analog clock, the clockwork gnomes inside digital clocks have to frantically push and pull a lever at 32.768KHz, and their stiff little pointy silk hats make perfect tweeter elements. It's also why those clocks get so warm, and why the snooze button is so unreliable; the gnome gets a well deserved nap, but is so exhausted he sleeps through his own alarm...

Re: Why we're blind to the color blue

#200

Post by domdib » Sat, Jul 17, 2021, 11:07 AM UTC

the_af wrote: post #143

thom wrote: post #123

Earlier quoted context omitted.

I found that episode very moving. It captured the feeling I suspect many of us experience, of having started out with simple, blissful naivety, before slowly accreting layers of grown up, professional bullshit until a craft loses its joy. The desire to strip it all away, not just the ways in which your work has changed over the years but also the ways in which it has changed you. I had no idea Alastair Reynolds was b…

Apparently more than one "Love, Death + Robots" episode was based on Alastair Reynolds' work. "Beyond the Aquila Rift", for example. I also spotted references to other scifi authors. There's one episode from the first season that is almost 100% something Bradbury would have written (without me telling you which one, can you guess which episode I'm thinking of? Just to doublecheck my own perception), and of course "Po…

John Scalzi authored at least one episode in the first season, and I think another in the second.