are more red to me.

eggplant more blue.

flora, honeydew -> yellow.

... so when I look at this or other similar charts, I see the same bands of colors repeating 2-3 times.

My vision reports 2 identical blue sections with an extra 3rd one of a different shade.

A repeating pattern from Salmon to Sea Foam.

And the reds fall closer to black and deep grays.

The article says, "...because perceiving color is a personal experience, (the tetrachromats) would have no way of knowing they see far beyond what we consider the limits of human vision.

I don't think that's at all true. Tetrachromats should be hugely dissatisfied with computer monitors, color television, color printing, color photographs -- our entire world of tri-stimulus color media. All such media wouldn't look just a little bit off, they would be grossly inaccurate in their reproduction of many of colors these people could see directly with their eyes.

I think their own dissatisfaction would stand out pretty clearly when they hear other people praising the quality of a new TV or a photograph that looks crappy to their eyes, or when they look at at touched-up paint jobs that everyone else thinks looks good, but where they see very clear and messy blobs of mismatched color.

EDIT: On further reading the article, is seems like the difference in color perception needs training otherwise those possessing this ability ignore it. It could also be that the brain doesn't typically process the signals from the mutant cones as a separate channel of information from the information coming from close-but-not-quite-the-same cones.

for the scientists to research whether any of the current fighter pilots are tetrachromats.

Color vision is X-linked. That's why men are around 100 times more likely to be color blind. Tetrachromacy would require a "normal" set of trichromatic genes and an "altered" set that allow for tetrachromacy. An altered set on it's own would merely result in a different perception of the hues trichromats can see rather than superior vision.

Think of it as the difference between a camera's lens and a camera's film.

The gene for one of the cones lies on the X chromosome -- tetrachromats would have two copies, and if they differ significantly then both copies would be expressed.

Men, having only one X chromosome, cannot be tetrachromats. Though depending on what X chromosome any particular man inherited from his mother, he might see a different set of 1 million colors than a man who inherited an X chromosome with a different variation of the cone gene.

Birds, insects, and even turtles can do it, so why can't I just get gene therapy to see light at ultraviolet wavelengths?

Particularly people who have had cataract surgery. It appears that in some cases the artificial lens implants people get don't filter out as much of the UV as a natural lens does.

This isn't tetrachromacy, of course. The extra UV that gets through apparently acts like extra blue light as far as the effect on the colors you see.

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(Shity outlook) Common ailment with republicans. He also has Bovine Oral Rectitus which leaks out uncontrollably.

I took this test once at work and only got two wrong out of one hundred.

http://www.xrite.com/custom_page.aspx?pageid=77&lang=en

Not surprising as I already knew I was colorblind, haha.

I'm going to have my mom and my daughter take it, as I'm convinced they see more colors or colors more clearly than most do.

I knew the three I got wrong were out of order, but no amount of shuffling looked right.

My wife is going to give me so much shit over this. She already says I'm not allowed to teach our 2-yr old colors

I scored a zero on it. Perfect color vision.

The red and green cones have a huge overlap in the colors they respond to. From wikipedia:

...

The opsins (photopigments) present in the L and M cones are encoded on the X chromosome; defective encoding of these leads to the two most common forms of color blindness. The OPN1LW gene, which codes for the opsin present in the L cones, is highly polymorphic (a recent study by Verrelli and Tishkoff found 85 variants in a sample of 236 men[9]). A very small percentage of women may have an extra type of color receptor because they have different alleles for the gene for the L opsin on each X chromosome. X chromosome inactivation means that only one opsin is expressed in each cone cell, and some women may therefore show a degree of tetrachromatic color vision.[10] Variations in OPN1MW, which codes the opsin expressed in M cones, appear to be rare, and the observed variants have no effect on spectral sensitivity.

...

While the implication seems to be that the fourth cone would peak in that green-yellow range, the lack of research in the area can't rule out other possibilities.

... nearer to green than normal.

Of course, with the red cone being highly polymorphic, there are probably women with different spectral versions of tetrachromatic vision. That difference could explain why most of the women they suspect have this vision haven't tested positive for it.

Our fury distant ancestors lost two of their color receptors. Skulking about at night, maybe they weren't using them.

Our great ape ancestors regained trichromacy in a forking of the remaining red-green receptor.

The peak sensitivities of reptile and bird color receptors are evenly spaced.



http://en.wikipedia.org/wiki/Bird_vision

and what they found was pretty interesting.

They did locate a woman with this ability. She happened to be an interior designer.

They gave her several swatches of color to look at. All seemed, to the average viewer, to be the same color. However, when she viewed them, she was able to pick out the subtle differences in each as if they all were completely different colors.

But then something interesting happened. They asked a male artist to take the same test. He was also able to see the differences in color with the same accuracy as the woman.

The conclusion they came to was: while some woman may have this as an innate ability, it appears as if a person can also learn to hone their own ability.

Given the fact that the guy was an artist and is looking at color all day long, it could be the difference between someone who plays a piano as apposed to some who is a accomplished pianist.

The more you deal with color the better you get at seeing the various differences.

It all makes sense now.