Why does mixing blue and yellow create green?

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Mixing blue and yellow paints typically produces green due to the way pigments absorb and reflect light. The discussion explores two options: one suggesting that the mixture absorbs all wavelengths from both colors, and another proposing that the mixture retains some reflective properties of each pigment. If the first option were true, mixing yellow and blue would result in black, while the second option implies that the pigments reflect a combination of colors, allowing for the creation of green. The conversation highlights the complexity of subtractive color mixing and the imperfections in pigment absorption, suggesting that real-world results may differ from theoretical models. Ultimately, the discussion emphasizes the need for a deeper understanding of pigment behavior to clarify how colors are produced through mixing.
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I am curious about how mixing paints works. If I mix an ideal paint A and an ideal paint B what is the product mixture C? Is it (Option 1) a mixture absorbs all the range A absorbs and absorbs all the range B absorbs OR is it (Option 2) a mixture with original A and B pigments therefore some pigments reflecting what A reflects and some pigments reflecting what B reflects.

If the Option 1 is true then it would not be possible to get a colour like orange with cyan-magenta-yellow model as mixing magenta and yellow would create something absorbs both green and blue. The product would be red.

If the Option 2 is true then I wonder how is it possible to get a red colour. As in this option mixing magenta and yellow would create a mixture with pigments reflecting blue & red and pigments reflecting green & red. The product must be something like (R:255, G:128, B:128), as all the pigments are reflecting red, half of them reflecting blue and half of them reflecting green.

Also from my childhood I remember mixing yellow and blue and getting a greenish colour. When I study the subtractive model it does not make sense.

If we consider the Option 1 is true then it means mixing yellow (absorbs blue) and blue (absorbs red and green) should make it black. If Option 2 is true I should have something reflecting all the primary colours and get a white or gray. Why mixing blue and yellow makes green? Is it because the pigments are not ideal?
 
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kuruman said:

Thanks for the link. I agree that full level of yellow and a partial level of magenta creates orange. However my problem is rather on the mechanisms of the paint mixing.

My questions are basically:

* How do I get orange by mixing yellow and magenta, in other words if magenta absorbs the green light how does the mixture reflects some?
* How do I get red by mixing yellow and magenta, what makes the mixture absorbing all the green light?
 
I think subtractive absorption seems to be simply placing bandpass filters in series. These filters are very broad and imperfect. It is difficult to talk through results unless we have the response curves for the filters and the wavelengths being applied. The colour printing experts seem to have been able to work it all out.
 
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