crocodile deathroll

Many years ago in the days of black and white TV was intrigued by this wheel. A professor performed a little experiment and said "I am going to give you a preview of color television" so he spun this Benham's disk wheel and low and behold color! I could not believe my eyes. Color right there on my black and white TV.
Many years later I tried the same experiment for myself put the wheel on an electric drill and videoed it and played it back on the TV with the color turn right down. Still color, lots of colors.
Then I tried a different tack. I thought this color may be just an optical illusion. If so, if I mount it on a electric drill and photographic with a low shutter speed then there should be no evidence of color on the print.
So I did that and much as I expected there was no color. So the color on the Benham's disc wheel truly was an optical illusion.
This may also imply that all color is subjective and in reality they are just varying wave lengths. It is only our minds the give a perception of color.

philechat

I believe the perceptual theory of color has been around as early as the beginning of 19th century, since the English poet Percy Bysshe Shelley wrote something akin to "the real world in itself is without color" in one of his essays ("On life" maybe?) and actually put the theory in practice in stanza 52 of "Adonais" and his sonnet "lift not the painted veil which those who live". Modern research on metamers (the mixture of different light wavelengths giving rise to the same perception) and differntial illumination ("white" perception in dim and noonday light, despite a difference of illumination of 1000x) confirms the hypotheses.

I would argue that "love" and "religious experience" could also be studied like color perception, since in my opinion they should be relegated to perceptual terms, and not be associacted with any external, physical "realities" (other than the [source of a different nature's] activation of the nervous system, and a change in conscious experience)

Perhaps we can anticipate a "color theory" of love (and other emotions) in near future?

[ December 16, 2002: Message edited by: philechat ]</p>

crocodile deathroll

Try this experiment for yourself.
Print it,
Then cut out this black and white disk.
Mount it on a stiff round piece of card the same size.
Pierce a needle through its center.
Then spin it as hard as you can.

Tell us what you see.

Jackalope

Better yet, the sunlight that we perceive as "white" falls in the yellow-green band of the spectrum. When I took bio classes in college, one of the things we did was find the peak absorption points for different types of chlorophyll. Biggest peak was right where you'd expect it if you knew our sun is actually yellow-green. But we still see sunlight as "white" in most situations.

For that matter, tungsten lights will distort colors on uncorrected filmstock. But your eyes will still the red apple under the lights. The brain does a hell of a of lot processing before you actually "see" something. For that matter, the eye is a pretty crappy camera. The image that forms on the back of the retina is damn blurry. The brain does a whole lot of cleanup.

I unfortunately haven't been able to locate an online photo of an image on the retina. Neurology and psychobiology textbooks include them pretty routinely, but I can't find an online one (and I don't have a scanner).

Shadowy Man

Well, the sun emits light at all wavelengths that are visible. It just happens to peak at about 500 nm.

scigirl

Croc--

Just because our senses can be fooled does NOT mean that there is NO true quantitative difference between the light reflections of a red pen and of a blue pen.

Unless of course all the spectrometry machines I used in grad school were just lying to me!

Hope that clears things up...

scigirl

[edited to add a "NOT"]

[ December 17, 2002: Message edited by: scigirl ]</p>

philechat

There is a difference between the spectrum of red and blue light. But the perception of "color" and "intensity" is qualitatively different (that is, different by essential property) from the spectrum wavelength and energy level of light.

Perception is best described as the interaction of an object and the mind, which is different from the properties of the object in-itself. Therefore, "red" does not exist unless perceived by a non-colorblind person.

It is one reason why phenomenology is a more sensible approach than a purely "physical" description of the natural world.

Kosh

I once wrote a story joking that everybody actually had the same favorite color, but everybody intrepets the "data" differently, so one persons red is another persons blue.

However, I think I'll use the lack of color in reality to explain to my wife why I prefer black lingerie....

Clutch

As I understand it, colour ain't all in the environment, and it ain't all your head either. It is partially subjectively constituted, but no less factual for all that.
<a href="http://www.hhmi.org/senses/b140.html" target="_blank">A primer on colour</a>

There are also top-down cognitive interference effects that can affect a colour judgement.

Living Dead Chipmunk

Everything my mom and I saw as dark red, my dad would call purple. We never figured out if it was a problem with learning the wrong name for a color, or if he really saw it differently.