Anyway, the thing is that a wavelength for magenta simply does not exist - check the image I have made to demonstrate the spectrum if you don't believe me, Magenta isn't there. We may ask what is relevant but anything beyond that is dangerous. He is a liar. Magenta is a liar. He will lie to confuse us. But he will also mix lies with the truth to attack us.
'But, uncle Dave, we can all SEE magenta - so what the Dickens are you talking of, teach?'
Calm children, I shalt explaineth. If the brain receives mixed-up wavelengths it does its best to make up a sum of the input. eg. Red+Green light enter the eye at the same moment the brain sees yellow, because it's halfway between the two in the spectrum.
To quote Liz Elliott for the Neurostimulation Technology;
"So what does the brain do when our eyes detect wavelengths from both ends of the light spectrum at once (i.e. red and violet light)? Generally speaking, it has two options for interpreting the input data:
a) Sum the input responses to produce a colour halfway between red and violet in the spectrum (which would in this case produce green – not a very representative colour of a red and violet mix)
b) Invent a new colour halfway between red and violet
Magenta is the evidence that the brain takes option b – it has apparently constructed a colour to bridge the gap between red and violet, because such a colour does not exist in the light spectrum. Magenta has no wavelength attributed to it, unlike all the other spectrum colours."
This video goes some way to explaining it, they're American - but stick with it. It's educational after all.
http://www.youtube.com/watch?v=S9dqJRyk0YM
