So according to my girlfriends professor a black car is really not black.
Because of the conjugation of the double bonds in black things. The wavelength of black things is so great its hard to have black at room temperature. You need extreme temperatures so its easier to just paint it red or blue and human eyes cant tell the difference. Is that true?

 

I'll need to see further scientific advice... Radmanly, where you be?

Of all the professors I've had, this is the first I've heard of it.

 

Is your girlfriend taking a photochemistry class?

I suppose if you want to define "black" as "pure black" or "absolute black" then her professor may well be right. But I don't understand the statement about just painting a car red or blue because human eyes can't tell the difference. What difference? Between red, blue, and black? (No, I don't think that's what he meant, for the record) Or between different tones of black? Back in my days in the printing ink business we always dealt with color spectrometry for pigment matching, final color matching for critical work, etc. Color theory and the descriptors used can be confusing when you first start with this - is there too much black in that yellow, is that green too blue, is that a warm gray or cool gray, do you want a clean red or a dirty red, etc. A well trained eye can discern very fine color differences, just as a well trained palette can discern fine differences in taste. Then there's the complication of metamerism, whereby a color sample will appear to change under varying light conditions depending on the pigments used to create the color. This is more than the wavelength of ambient light altering tones on colors (think of a camera where the white balance is off and all colors look skewed), but it deals with how different pigments interact with different wavelengths of light. Two colors can match perfectly under light of a certain temperature, yet be several shades different when the light changes. The light is effecting the various pigments in different ways. It's not just the "visible color" - it goes way deeper than that. I suspect your girlfriend's prof is talking something along those lines.

But that doesn't mean you shouldn't paint a car black!

 

Color is related to the frequency of the light,be it generated by an LED or laser pointer or reflected by an object illuminated under a full spectrum light like white. Remember our sun is about 10,000 degrees at the surface and hotter several million further inside, but it is not white, you go Superman, its sorta yellow.

Black is often defined as the absense of light or the object that does not reflect light. A black body like a lump of coal pretty much adsorbes all light and reflects none, thus is black.

A piece of blackened metal does radiate light at long or low wavelengths that relate to it temperature and can be easily measured with a simple temp gun. We dont see infrared but it is there especially at 904 nm wavelengths which we call OH SHIRT he's got my speed............DAM. Take a blackened object and heat it to about 2000 f and youll see the redish hue due to the radiated light being within out sensory range, and we call it light. Were defective in that if we dont see it we sorta discount its presense or significance, like IR,, UV light and so forth.

For me Black is the appearance of an object that does not reflect light or the absense of light like at night or in the middle of political campaigns. My car is black and the hood is darker, as it does not reflect any light and has a matt finish that does not have a visible sheen. Ie no reflections from the front of my crossfires body.

Like Mick said, Paint it Black. THE END.

Woody

 

Woody you're a hoot