Why are we able to see things in different colors, shades and textures?

[Achilles]

Like why is my desk brown, why is my laptop black, why can I see all these things in difference colors, shades, textures and detail.

My hypothesis is simply that electrons absorb and emit electromagnetic waves to our eyes. Is this true?

[swansont]

A combination of two things, mainly: the various colors they reflect or emit (lots of physics here), and how your eyes work (lots of biology here).  

[beecee]

5 hours ago, Achilles said:

Like why is my desk brown, why is my laptop black, why can I see all these things in difference colors, shades, textures and detail.

My hypothesis is simply that electrons absorb and emit electromagnetic waves to our eyes. Is this true?

The colour of anything in the first instant, is due to the nature and part of the EMS that enters the eyes.

[koti]

6 hours ago, Achilles said:

Like why is my desk brown, why is my laptop black, why can I see all these things in difference colors, shades, textures and detail.

My hypothesis is simply that electrons absorb and emit electromagnetic waves to our eyes. Is this true?

Browse the below document, you will find a lot of information you are looking for in it. If you have any questions after reading the document I will try to answer them.

https://www.heidelberg.com/global/media/en/global_media/products___prinect_topics/pdf_1/color_quality.pdf

Edited August 20, 2018 by koti

[Itoero]

22 hours ago, Achilles said:

Like why is my desk brown, why is my laptop black, why can I see all these things in difference colors, shades, textures and detail.

My hypothesis is simply that electrons absorb and emit electromagnetic waves to our eyes. Is this true?

We  (proteins in photoreceptor cells) absorb photons from scattered light. The colour you observe from your desk and laptop is due to which light get's absorbed and which light gets reflected.

[mistermack]

23 hours ago, Achilles said:

Like why is my desk brown, why is my laptop black, why can I see all these things in difference colors, shades, textures and detail.

My hypothesis is simply that electrons absorb and emit electromagnetic waves to our eyes. Is this true?

The Sun gives out light in all the visible wavelengths. Our eyes see the combination of all that as very nearly white. 

When that light combination falls on a red object, most of the light is absorbed, and what bounces back is the red wavelengths, so that's what we see. Same goes for green, brown, blue etc. You are seeing what didn't get absorbed, but was reflected. 

Light that gets absorbed, and re-emitted is called fluorescence. It's not what you see from everyday objects, that's usually reflected light. 

[swansont]

54 minutes ago, mistermack said:

The Sun gives out light in all the visible wavelengths. Our eyes see the combination of all that as very nearly white. 

When that light combination falls on a red object, most of the light is absorbed, and what bounces back is the red wavelengths, so that's what we see. Same goes for green, brown, blue etc. You are seeing what didn't get absorbed, but was reflected. 

Except there is no wavelength that corresponds to brown.

And if you have multiple colors, you can perceive it as another color, e.g. red and yellow looks orange, but you can't tell if there are two colors of light or one.

Both are because of what is happening in the vision system when you have multiple wavelengths.

[StringJunky]

5 minutes ago, swansont said:

And if you have multiple colors, you can perceive it as another color, e.g. red and yellow looks orange, but you can't tell if there are two colors of light or one.

Is orange not some kind of product of red and yellow, rather than a pure colour? I'm thinking of the order of a rainbow, and orange is between those two.

Edited August 21, 2018 by StringJunky

[koti]

4 minutes ago, StringJunky said:

Is orange not some kind of product of red and yellow, rather than a pure colour? I'm thinking of the order of a rainbow, and orange is between those two.

Orange, like any other color is subjective and depends on system used and personal perception which always varies. Orange on aluminium (RAL color management system) will look very different from printed orange (Pantone system for example) on paper due to light bouncing off and being absorbed differently from those two surfaces. The pure colors are called „primary colors” and are dependant on the system used. You can mix red+yellow from RGB color pallet and see orange...untill you shine blue light on it and it will no longer be orange. On top of that, you will perceive a different orange from me while we’re looking at the same orange object under the same conditions - there are ways of testing that, but yes, if you mix red+yellow you will get orange - more or less. Light is like swansont said a bit tricky colorwise. You can pinpoint a certain wavelength from within the visible spectrum and call it „oragne” but only from within a certain color management system. You change the system and the results will change so there is no universal orange. If that doesn’t make sense don’t worry, just keep in mind that everybody sees a little bit different „orange”

[MigL]

It should also be mentioned that, with emitted light the 'primary' colors are Red, Blue, Green ( hence the RGB of the phosphor dots on a monitor ) and are additive, such that all three make white light.
With reflected colors., such as paint, the primary colors are Red, Blue, Yellow. And because of the absorption/reflection, a combination of the three yields Black ( more like brown ), or an absence of color information reaching your eyes.
( actualy the colors are cyan, magenta, and yellow, but I'm a guy, we don't know taupe, lavender or emerald either )

[swansont]

1 hour ago, StringJunky said:

Is orange not some kind of product of red and yellow, rather than a pure colour? I'm thinking of the order of a rainbow, and orange is between those two.

 Orange is the "O" in ROY G BIV. It is its own color. Or a combination, as I said.

Roughly 590 - 635 nm

[StringJunky]

38 minutes ago, swansont said:

 Orange is the "O" in ROY G BIV. It is its own color. Or a combination, as I said.

Roughly 590 - 635 nm

I know. Never mind. I can't get across what I'm thinking. I find it problematic  because it's so tied with our physiology and I have difficulty separating my perception from the external or objective properties.

[swansont]

17 hours ago, StringJunky said:

I know. Never mind. I can't get across what I'm thinking. I find it problematic  because it's so tied with our physiology and I have difficulty separating my perception from the external or objective properties.

We have primary and secondary colors, but that’s tied in with the physiology as well. As are colors like gold and silver.

But any color in the spectrum can be represented by a single wavelength 

(nothing rhymes with orange but that’s neither phyics nor physiology)

[StringJunky]

49 minutes ago, swansont said:

We have primary and secondary colors, but that’s tied in with the physiology as well. As are colors like gold and silver.

But any color in the spectrum can be represented by a single wavelength 

(nothing rhymes with orange but that’s neither phyics nor physiology)

Right. Is there a relationship with the frequency or wavelength that tells you what colour will result when you combine two spectral colours? I'm talking about light, not pigments. For instance, if we mix green light with red light we get yellow. Can we predict mathematically the result?

Edited August 22, 2018 by StringJunky

[mistermack]

4 hours ago, StringJunky said:

Right. Is there a relationship with the frequency or wavelength that tells you what colour will result when you combine two spectral colours? I'm talking about light, not pigments. For instance, if we mix green light with red light we get yellow. Can we predict mathematically the result?

If you can, I think it's probably coincidence. The reason you see orange, is because the light receptors in your eyes give a certain signal. It probably happens that a mix of red and yellow light cause the same signal to be sent as when orange light of just one wavelength hit's the retina. I suppose you might be able to get mathematical with the dimensions of the cones. Or maybe it's possible that the mixing is done in the brain, when red and yellow signals come in. 

It would take some research to find out how it happens.

Edited August 22, 2018 by mistermack