Is it possible that our eyes are unable to see another color, and no I’m not talking about infrared, etc. Another pigment or light color… Is it fathomable?
Just an offhand guess, but I’d imagine that we cannot see most colors. Our brains “round them off” to the nearest color which we are able to process.
However, we have other ways of distinguishing one color from another-- mathematics. We know the frequencies of the entire range of visible light, and anything outside that range is invisible to us.
So, while our minds may not be able to actually distinguish between 4.90000110[sup]14[/sup] and 4.90000210[sup]14[/sup] Hz, we know that they’re both “red”.
-David
What makes you think infared and ultraviolet aren’t colors in their own right? Infared cameras pick it up as a color. Perhaps there is an animal somewhere that sees it as a color–or if not, then perhaps it is at least plausible.
Good points, Jim B.. IIRC, wolves and dogs (and probably some other animals) can see into a portion of the infrared spectrum.
OTOH, they normally only see in shades of grey, though…
-David
AFAIK the human eye can see the entire spectrum between infrared and ultraviolet; it’s a constant spectrum without any gaps. The problem is nomenclature, not the perception. Your eye can clearly see the difference between a very bright and a slightly less bright red (maybe not if the difference in frequency is as little as in SoulFrost’s example), but you call it “red” without distinction because we lack terms to describe every nuance we see.
The interesting thing, however, is that color nomenclature is entirely arbitrary. The Choctaw, I read, use the same word for bright green and bright blue and another one for deep green and deep blue.
This Cecil column might be of interest: http://www.straightdope.com/classics/a2_168b.html
Well you can see more colours if you’re a tetrachromat. (4 colour channels)
That link also says “Some butterflies go one better and are actually pentachromats with five different types of colour sensor”
BTW, for most of us, the only colours we can detect are red, green and blue because of our three kinds of “cones” in our retinas. When we see yellow, our red and green detectors are being triggered - which is how a digital camera or scanner works. We can’t tell the difference between pure yellow light and a mixture of red and green light - or orange and lime light.
Tetrachromats might be able to do that though.
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/specol.html#c1
That shows the visible colour spectrum. It shows that light can be pure yellow, or be a mixture of red and green light and appear to be yellow to us. (Since we don’t have a yellow detector - just red, green and blue)
If you want to exclude ultra violet and infra-red, that is, exclude colors not visible to the human eye, then no, humans can see all colors visible to the human eye. But what Schnitte about nomenclature can get very interesting. I studied that for a week or two in a cross culture psychology class. When you don’t have a word for something like that, you tend not to notice it, it just get’s grouped in with other things. Out big example was the eskimos and snow. People in tropical areas, I would imagine barely think about snow, much less differentiate different types of snow. People in the midwest know of several different types of snow (wet snow, powder etc…) whereas the eskimos have something like 20 different words to describe snow (good polor bear hunting snow for example). Now hear in milwaukee I it may snow two days in a row, one day it might be bad snow to hunt bears in and the next day it may be good snow to hunt bears in, but since I didn’t grow up needing to be aware of that they may both just be wet snow. There may very well be a difference between the to snows, but I just don’t notice it (sensed it but did not percieve it), due to the fact that they’ve never been differentiated. Come to think of it, we talked about exactly your question in our class. We discussed groups of people who do not differentiate between blue and green. To us in America we have blue, green, blue-green and so on, but to this group if you show them something that is anyone of those colors they will call them all the same thing. If they grow up their whole life calling all those things the same thing, and have no need whatsoever to differentiate the different colors then they start to percieve them as the same thing. Their brain groups them all into one category to make them easier and quicker to recall. I hope this all makes sense, I started rambling and felt like I was writing an essay for that psych class. Just ignore this post if it doens’t make any sense.
Reading Cecil’s article: “if they have 2 words…5 words…7 words for colors”, I got to thinking about the joy of visiting a paint store and all the different names they have for colors.
So, I guess at Sherwin-Williams alone we’ve discovered 1000 new colors. :eek:
My first wife was an artist, and very precise about her colors. we had conversations that went something like this.
What are you looking for?
My red shoes.
You mean these?
Those are maroon.
These?
Those are bugundy.
How about these?
Those are carmine.
And on and on and on. To me they all looked “red” but to her they were all separate colors.
This story is actually a good example of several things, and if you’re interested you could check out a book called The Great Eskimo Word Hoax.
In the meantime you can amuse yourself by noting the arbitrarily different number of “words for snow” the Eskimos are supposed to have each time the story is told.
Dammit, if I had checked before I posted I would have got the title right. It’s The Great Eskimo Vocabulary Hoax by Geoffrey K Pullum.
You should also keep in mind that our combinations of primary colors (blue, green, and red) will appear differently to other creatures which have greater or lesser sensitivity to certain wavelengths.
There is an entymological concept called “bee purple.” In humans, the ends of the visible spectrum are red and blue. Combine them, and you get purple. In bees, the ends of the spectrum are ultraviolet and yellow. The color of these two combined would look yellow to us, but distinct from either yellow or UV to bees. Meanwhile, our purple would simply look blue to bees.
Further to that I saw a very interesting doco on bees once. They tried to simulate a bee’s vision - in terms of field of vision, with the bee buzzing along, and with the bees colour range - as though the camera lens was the bee’s eyes if you get me. The world was all yellow and blue and purple, quite lovely.
In what part of the spectrum are the colors that can only be seen in blacklight? Could someone please explain it?
Those colors are just what they look like. Lime green and magenta concert posters from the 60s are… lime green and magenta. The glowing blue hand stamp you got at the jazz club is actually the color blue.
Fluorescent colors are light emitters rather than light reflectors. They are like light bulbs and LEDs: they require a power supply to drive them. That power supply is light, but light of some other color. In many cases it need not be UV. If you have a blue LED flashlight on your keychain, try shining it on objects at night. In that pure blue light, everything should be blue, but you’ll see yellow and red fluorescent dyes on food containers. Those dyes absorb the blue light, then they use it to power their red or yellow glow.
It all depends on what you mean by “color”.
There are monochromatic colors, colors formed by a single wavelength of emitted light, as from a laser or LED. Monochromatic light is rare in nature, but is quite common in our technological age, with the ubiquitousness of televisions and LEDs.
Then there are blackbody colors, wide-spectrum radiation emitted a (ideal) heated object. Different temperatures yield different colors, from invisible infrared through red, yellow, white, and blue-white.
Then you get filtered colors, colors formed by subtracting a range of frequencies from (usually) broad-spectrum white light, either by filtered transmission through an object or by selective reflection off an object. The vast majority of perceived colors are filtered colors.
There are also combined colors, which occur when two monochromatic light sources are brought together. This is important because it’s the basis for color television.
All colors can be expressed in the form of an spectral distribution curve, which is just a graph of the relative number of photons at each frequency in the visual range. By applying the spectral distribution curve against the spectral efficiency function of each of the three visual receptors in the eye (the red, green, and blue cones), any particular distribution can be reduced to a “tristimulus value” of three values indicating how much that distribution would stimulate the three receptor sets in the human eye. Two different distributions that reduce to the same tristimulus values would be indistinguishable – to that individual.
Different people, however, have different spectral efficiency functions for their visual receptors. Most people have three types of receptors. However, some have four (the elusive “tetrachromat”), and others have two or even one (various forms of color blindness). Still more have three, but two of them are so close in behavior that they are barely differentiable and thus act as if they were the same.
A tetrachromat would be able to distinguish as different two distributions (e.g. monochrome yellow as opposed to a red-green bichromic blend) that appear identical to a typical trichromat. As such, it is likely that tetrachromats would identify “extra” colors that trichromats would not. However, these are not “new” colors, just new names for existing colors.
So, no, there really can’t be any new “colors”, just new names for existing colors.
bought my “doors” fanatic daughter a shirt that said, “i am wearing black until something darker comes along.”
We see the spectrum that we do because we have adapted to possess cells sensitive to certain colors/frequencies. It’s no accident that the frequencies that nature has chosen us to be sensitive to are some of those which illuminate the Earth the best (I couldn’t find the site I wanted but here’s a pretty picture). Notice that the visible spectrum is the high end of the only strong high-energy band that illuminates the earth. No coincidence there.
As to why we see the colors that we do, it’s mostly in our brain wiring. Our tendency to see the near red and the far violet to be the same magenta has caused us to design the color wheel, linking all the subjective hues in a circle when red and violet are the furthest apart of any in the visible spectrum. This has to do with some physiological aspect of our ability to distinguish color in low-light situations (such as the inside of a cave).
Bees might be able to see many frequencies that we don’t, but how many bumble bees can paint?