Forbidden Colors

January 23, 2012 4:07 AM

"The observers of this unusual visual stimulus reported seeing the borders between the stripes gradually disappear, and the colors seem to flood into each other. Amazingly, the image seemed to override their eyes' opponency mechanism, and they said they perceived colors they'd never seen before."
posted by Slap*Happy (30 comments total)

Since I love you, here's Lovecraft's "The Colour out of Space."
posted by Slap*Happy at 4:12 AM on January 23 [4 favorites]

"While most colors induce a mixture of effects in both sets of neurons, which our brains can decode to identify the component parts, red light exactly cancels the effect of green light (and yellow exactly cancels blue), so we can never perceive those colors coming from the same place."

Ran that red light? What do you mean, officer? It looked green to me. You see, while most colors induce a mixture.....
posted by three blind mice at 4:22 AM on January 23 [4 favorites]

In the future, sites will be designed with retinaltracker.js.
posted by michaelh at 4:35 AM on January 23 [3 favorites]

Drat. I was hoping for octarine to appear in that article.
posted by Jubal Kessler at 4:41 AM on January 23 [8 favorites]

Billock argues that Hsieh's study failed to generate the colors because it left out a key component of the setup: eye trackers. Hsieh merely had volunteers fix their gaze on striped images; he didn't use retinal stabilization.

Not to mention the assumption that being able to perceive a color means you are able to generate that color on a computer. I can't even generate normal, legal colors using those palette tool things. I'm all "maybe...more yellow? no wait, that made purple...." Needless to say, I'm perfectly able to perceive color.
posted by DU at 4:50 AM on January 23 [3 favorites]

Where was this link a couple weeks ago?
posted by Jpfed at 5:02 AM on January 23

Jubal Kessler: Drat. I was hoping for octarine to appear in that article.

When I was a kid I read The Colour of Magic. When octarine was described, I thought about it, and realized that it wasn't a color in the real world. The next day, while walking to school, I started to think about it again, trying to see it in my mind's eye and suddenly it was there. I've been able to recall that color ever since.
posted by Kattullus at 5:11 AM on January 23

I love when I go to Google to look up 'octarine' and get pointed to AskMeFi.
posted by MtDewd at 5:29 AM on January 23 [2 favorites]

Here's something I found years ago that lets you see further into both cyan and green than you ever normally can. Because the cones in our eyes overlap in frequency ranges, some colors can't normally be seen except by temporarily wearing out one of your cones. Try it, it's really pretty cool.
posted by MythMaker at 5:29 AM on January 23 [22 favorites]

So my first question was "when do I get this on my iphone?" Here is a blog that says,

Upgraded video components make the iPhone 4 one step closer to having the ability to add eye tracking. Maybe all that needs to be done is create an iPhone app that is able to perform pupil recognition using the live video stream of a person’s face.
posted by bitslayer at 5:33 AM on January 23

Wonderful.

It reminds me of Borges' microfiction, "The Fauna of Mirrors"

... One night the mirror people invaded the earth. Their power was great, but at the end of bloody warfare the magic arts of the Yellow Emperor prevailed. He repulsed the invaders, imprisoned them in their mirrors, and forced on them the task of repeating, as though in a kind of dream, all the actions of men. He stripped them of their power and of their forms and reduced them to mere slavish reflections.

Nonetheless, a day will come when the magic spell will be shaken off. The first to awaken will be the Fish. Deep in the mirror we will perceive a very faint line and the color of this line will be like no other color. Later on, other shapes will begin to stir. Little by little they will differ from us; little by little they will not imitate us. They will break through the barriers of glass or metal and this time will not be defeated...
posted by lucien_reeve at 5:41 AM on January 23 [8 favorites]

In school we called these imaginary colors, since their coordinates in color space may be imaginary numbers. I think Imaginary Colors would be an awesome band name.
posted by miyabo at 6:05 AM on January 23 [1 favorite]

I'm looking forward to the day Metafilter is presented on a professional breen background.
posted by panboi at 6:19 AM on January 23 [6 favorites]

Slaanesh is pleased.
posted by Sternmeyer at 6:19 AM on January 23 [3 favorites]

The wife and I agree on pretty much everything - movies, politics, breakfast cereals. but the colour of that green, no blue, no green, no for fuck's sake it's blue (it's actually green) dustpan will see us in divorce court one day.
posted by mattoxic at 6:39 AM on January 23 [4 favorites]

Interesting. If you do the 'magic eye' thing on this image, I don't get green, I get like a scintillating field that goes back and forth between yellow and blue.
posted by empath at 6:44 AM on January 23

The wife and I agree on pretty much everything - movies, politics, breakfast cereals. but the colour of that green, no blue, no green, no for fuck's sake it's blue (it's actually green) dustpan will see us in divorce court one day.

Maybe it's just cyan?
posted by Jpfed at 7:22 AM on January 23 [1 favorite]

Interesting. If you do the 'magic eye' thing on this image, I don't get green, I get like a scintillating field that goes back and forth between yellow and blue.

That's because you see the blue square with your left eye and the yellow square with your right eye. So your eyes tell your brain: I see blue! No, wait, it's yellow! No, blue!
posted by sour cream at 7:31 AM on January 23 [1 favorite]

As someone with red-green color blindness, I can report that significant swaths of the spectrum are imaginary to me. ;)
posted by Celsius1414 at 8:18 AM on January 23 [1 favorite]

Paul Churchland has an alternative way of seeing 'chimerical colours' - he describes a method you can try out for yourself in this paper (pdf).
posted by Segundus at 8:27 AM on January 23 [4 favorites]

There was a nice article on a this topic (and what I think may be yet another method for seeing them that hasn't been referenced here yet) in the Feb 2010 edition of Scientific American - unfortunately, the complete text is only available to digital subscribers.

The method involves staring at a colored patch for a minute or more, and then looking at (I think) a white patch, and, as I'm sure you've guessed, involved exhaustion of the color receptors in the retina.
posted by kcds at 9:05 AM on January 23

I kept waiting for a Spinal tap quote in the Churchland paper.
posted by no relation at 9:15 AM on January 23

I came here to talk about Churchland's hyperbolic orange! The eye is a strange , strange thing.
posted by Earthtopus at 9:30 AM on January 23

I'm looking forward to the day Metafilter is presented on a professional breen background.

Pepsi-Amex breen?
posted by yoink at 9:36 AM on January 23

My parrot, apparently, can see colors that I can't. Parrots in general have a much broader visible spectrum than humans do.

My partner, on the other hand, is colorblind, and early on showed up for a date wearing a cherry red shirt and tomato-red pants. I still cringe at the thought.

Vision is a fascinating thing.
posted by kinnakeet at 10:43 AM on January 23 [1 favorite]

Was this effect really not known to scientists? They should have asked artists. I learned how to use this effect in painting classes. I have a huge painting on my wall that is primarily greens, but I used plenty of reddish greens. I was taught that if you mix complementary colors, you get a middle tone that is supposed to be gray but usually turns out an ugly brown because pigments are rarely precisely complimentary. But if, for example, you apply transparent green over a red, the light mixes as it reflects off the transparent pigment layers, giving a reddish green. There are other applications. Instead of "mixing the colors to death" to get that ugly brown, if you leave the pigments folded but not mixed together, when you brush them on, you get streaks of the colors mixed together. If you look closely, you can see the separation of the colors, but if you look from a distance, they blend together visually. There are also other techniques to get these colors to appear, notably "simultaneous contrast," which is much more related to what these scientists are trying to understand.

Barnett Newman was a master of this emergent color illusion. Those big black paintings all have a specific color. They're composed of dozens of carefully applied translucent colors. The light penetrates the surface and passes through the dozens of layers of color before it remerges to be seen by the eye. Upon first glance, the painting appears black. But if you look at it for a while, with a steady gaze, you will see the specific color that Newman intended. No, don't bother googling for some of his paintings, you can only see this effect in the original painting, not a reproduction.
posted by charlie don't surf at 11:18 AM on January 23 [4 favorites]

No mention of squant...
posted by klausness at 3:47 PM on January 23

I was intrigued by the Churchland paper, so I whipped up this browser-based version of the illusions.
posted by jepler at 6:30 PM on January 23 [4 favorites]

If you look closely, you can see the separation of the colors

I believe that the effect you're talking about is completely different from the effect that the original post is about.
posted by Jpfed at 7:11 AM on January 25

Jepler, all of your illusions are exactly the same for me in Firefox (green circle that disappears). Works in Safari though.
posted by mendel at 3:38 PM on January 29