Okay. I’ve actually been thinking about this more than my babysteps would suggest, but here’s what I understand/question so far:
So let’s say I have a natural fiber cotton shirt. I assume it would appear some kind of off-white, because of the manner in which the natural cotton (cellulose?) molecules reflect and absorb light.
Am I correct in assuming the light is coming in photons - little “packages” that contain all of the various frequencies. The extent to which something has color depends on the extent to which these photons interact with the substance’s molecues: each individual photon could either pass between different molecules, pass through a single molecule, or collide with a part of a molecule.
Dye actually affects the cotton molecules, either by sitting on top of the cotton molecules, or with more advanced dyes, binding with them.
So is it that the addition of the dye molecules to the natural cotton molecules changes the way the photons interact with the shirt at a molecular level? How exactly? Are the collisions more “complex” within more “complex” molecules, with light bouncing around inside and among them before being reflected back out?
You’ve said that a particular dye will rarely be a single color - the various hues of dye molecules will loose their bonds with the cotton on different schedules, resuting in fading over time.
If I dye a shirt red - which actually includes a little blue and yellow, will some red, blue, and yellow molecules attach to each cotton molecule, or will there be some red cotton molecules, some blue ones, and some yellow ones?
How about panache’s question - if I could see these dye molecules sitting on top of or bonded with the cotton molecules, would they appear red, or would they just appear as a structure that reflects red?
And how is it different if I dye the shirt, or if I paint it? How do the red paint molecules - which I assume primarily sit on top of the cotton fabric as a whole, differ from the molecular bonding of dye? I intended my OP to be about color, not dye, and used a shirt merely as an example.
Here’s a goofy thing I’m wondering - assume a certain color of “red” - which I assume would be most accurately described as a combination of various spectra. Are identical molecular reactions taking place in all objects that appear that color - whether made of fur, rubber, paint, plastic, etc.? Or are there multiple molecular “ways” that different objects can appear the same color? Does that even make sense as a question?
Another similar question: I assume a dye can be made out of either natural or manmade pigments. I also assume, however, that manmade vs natural dyes can be distinguished upon laboratory examination. But I assume the extent to which they appear to be the same color depends on the extent to which they absorb/reflect photons in the same manner. Let’s say I dye a piece of cotton and a piece of wool the same color, so that in a close-up photo they might appear indistinguishable. How would the “redness” differ at a molecular level?
Then I guess what we haven’t addressed is how I perceive certain wavelengths as color. I guess we have 3 color receptors in our eye like a TV (in the rods - or is it the cones?) I seem to recall that those color receptors don’t exactly correlate with the 3 primary colors, but that your brain “tricks” yourself into perceiving a certain combination as “blue.” And primates evolved such that we lost the ability to see things in UV and/or infrared, and that birds and insects see objects as appearing vastly different than we…
Final question - what the heck is going on with shiny metallic colors, like polished steel or gold?
Thanks again. I really appreciate your attemtps to help me make sense of this.