The colours of the Raimbow

[cacian]

How many are colours are there to the Rainbow?

I just want to check agaisnt your answers.


Is it possible to determine a set number of colours against a natural source of light such as the rainbow?

[TheFifthElement]

Curious question. Technically you can see all colours in the rainbow as a rainbow occurs when 'white' light is refracted (split) through the prism of falling water. However, accepted wisdom is that these resolve into 7 distinct bands being red, orange, yellow, green, blue, indigo, violet, but these are only the colours we perceive, or as we perceive them, and supposedly the human eye is only capable of perceiving the colours of red, green and blue and all other colour is achieved by a blend of those colours (or, in the case of black, an absence). Sort of, kind of. I'm not a scientist; someone with more/better scientific knowledge could probably explain it better and more correctly.

Colour vision is very much subjective and is still not entirely understood so I don't think there's really a truly definitive answer to your question.

Light, or should I say the electromagnetic spectrum, and everything associated with it is a fascinating, complex and wonderful subject. I wish I knew more about it :)

[Buh4Bee]

Fifth gave a wonderful answer, but this cannot be a serious question.

[NikolaiI]

well - physically, as fifth said, there are unlimited hues of the three basic primarys and their secondary colours - that is, yellow, blue, red; and purple, orange and green. Including the absolutes, white and black, at the end of the spectrum. But do you really see white and black in a rainbow?

But - in terms of what you usually see, I am not sure either.. 7? 8? I'd have to look it up.

[TheFifthElement]

But do you really see white and black in a rainbow?

Because a rainbow is created by refraction of light you wouldn't get black or white because, in that context, they are not colours but a presence or absence of light. White is all of the colours mashed together, so white light is refracted through water and the refraction displays the colours which are really different wavelengths of visible light. Black would be an absence of light.

But that's only in relation to light. When you're dealing with paints, for example, black and white would be colours.

[JuniperWoolf]

I'm told that it's our human brains that make the seven solid color distinctions. In actuality the rainbow is one continuous undivided spectrum that changes very gradually depending on the wavelength of the light.