So if you're looking for ways to hide data in an image, making slight adjustments to the blue channel isn't the worst idea.
Why we're blind to the color blue
111–120 of 218 posts
Re: Why we're blind to the color blue
#112I 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…
The author is correct. Lighting designers sometimes use the effect deliberately to create blue spotlights that viewers can't focus on. That description doesn't do it justice - you have to experience it to appreciate it. It's very striking and slightly surreal.
They might be correct about chromatic aberration and the difficultly of focusing on pure blue, but the conclusion from their experiment is completely wrong.
Re: Why we're blind to the color blue
#113Earlier quoted context omitted.
Indeed, green contributes more. Example of the Y channel after blurring r/g/b: https://imgur.com/a/3p15Qe1 And colured versions: https://imgur.com/a/Knq2Ue3 (image source: https://en.wikipedia.org/wiki/Flower#/media/File:Flower_post... )
More, as in 10 times more for green, and 3 times more for red. So it's true that we're pretty blind to blue, just the "focusing" explanation is not correct...
To be honest I need to rethink the arguments of the linked article - if we just use coloured filters in front of our eyes which exclude each channel, the image (I think) remains sharp (or at least that happens with red/cyan anaglyph glasses).
Re: Why we're blind to the color blue
#114That's complete bullshit. The image remains sharp because the red and green channel remain sharp. It's obvious that the entire image has a nasty yellow tint. This has nothing to do with chromatic aberration, try again.
Re: Why we're blind to the color blue
#115One 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://…
As mentioned above, it just looks different in person, that picture does not do it justice by any means. It's kinda like when you see a 3D render with inaccurate physics, but this one is in the real world - it feels out of place. Or like catching a really pink sunset: you can look at it for as long as you want and the color never ceases to impress you.
Re: Why we're blind to the color blue
#116There's an optometry place in my neighborhood with a back-lit sign with big, blue block letters. And every time I walk by at night I note how fuzzy it looks. I'm convinced this is an intentional troll. This optometrist knowingly picked a sign to make people momentarily question their vision.
This happens every wintertime for me as blue string lights are put up, and they always appear “fuzzy” compared to other colors.
Technology Connections did some videos on "Making Holiday Lights Less Garish", where instead of using narrowband colored LEDs he filtered white ones: https://www.youtube.com/watch?v=PBFPJ3_6ZWs
Re: Why we're blind to the color blue
#117Earlier quoted context omitted.
9 in 10 people have some affliction of astigmatism. Astigmatism is just that your eye isn’t perfectly spherical. What does your eye prescription say in the cyl and axis fields, that’s your astigmatism correction.
'eye prescription'? Bruh. Read the comment of mine you replied to. 20/10 and 20/13 vision. I don't need prescriptions.
That's like saying you can run a 3 minute mile so you don't have a shoe size.
This whole thread is silly.
Re: Why we're blind to the color blue
#118Earlier quoted context omitted.
9 in 10 people have some affliction of astigmatism. Astigmatism is just that your eye isn’t perfectly spherical. What does your eye prescription say in the cyl and axis fields, that’s your astigmatism correction.
'eye prescription'? Bruh. Read the comment of mine you replied to. 20/10 and 20/13 vision. I don't need prescriptions.
Aren't those numbers about your ability to focus on distance objects, though?
I could totally believe the someone might have "perfect" vision that doesn't require correction, but still have a slight astigmatism that impacts their vision under certain specific scenarios such as when viewing blue LEDs in low light.
I'm not necessarily saying that's what you have, but more just that to the extent your eyes have been evaluated, it was likely "yeah they look great as far as your ability to perceive the brightly lit eye chart, no need to do the more detailed analysis where we figure out the other parameters that will never be used because you're fine, bye."
Re: Why we're blind to the color blue
#119Earlier quoted context omitted.
HN is so funny. 'I have no astigmatism.' -- 'Sure you do!'
Because nearly every person has some amount of astigmatism.
Sure, but presumably the parent has been checked by their eye doctor and indeed, not everyone has it.
Signed, a dude with very slight astigmatism :)
Re: Why we're blind to the color blue
#120One 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…
Yes!! The lack of green-blue distinction is prevalent enough in linguistics that the term "grue" has entered the lexicon.
Paul and Kay (1969) argue for a linguistic universal which posits that the set of which colors a language has is a function of how many colors it has. (Stealing from https://en.wikipedia.org/wiki/Linguistic_relativity_and_the_...):
1. All languages contain terms for black and white. 2. If a language contains three terms, then it contains a term for red. 3. If a language contains four terms, then it contains a term for either green or yellow (but not both). 4. If a language contains five terms, then it contains terms for both green and yellow. 5. If a language contains six terms, then it contains a term for blue. 6. If a language contains seven terms, then it contains a term for brown. 7. If a language contains eight or more terms, then it contains terms for purple, pink, orange or gray.
The opposite of the grue phenomenon exists too, i.e. languages which subdivide the "blue" part of the spectrum into separate lexemes. In Russian, for instance, goluboy = light blue, whereas siniy = blue to dark blue. This morning I was reading the Wikipedia entry for color revolution, and there's a quote from Belarusian President Lukashenko, "They [the West] think that Belarus is ready for some 'orange' or, what is a rather frightening option, 'blue' or 'cornflower blue' revolution." I had to chuckle about that - it sounds so goofy in the English translation, but that's only because we don't have a lexical distinction there. (Now I would have personally translated it to light blue, but that's another matter.)