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Oh Violet, Lovely Violet, but I don't think much of Her Sister Magenta.


colinbm

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While nosing around the internet (waiting for a Panosonic G3 to arrive next week), I happened onto this discussion about my love for Violet & my distaste for Magenta.

Is this a scientific discussion, by experts, please ?

Cheers

Col

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Experts? We have experts here?? Who??? :D :P :( :) :lol:

 

There do seem to be some valid references and the discussion seems to explain a lot of interesting points. I think we should still be careful with internet references unless, of course, they reference peer-reviewed scientific papers in reputable journals. (Do I know what those are for this subject? No, I don't. But it could be discovered.)

 

The key point for me is that we have to differentiate between the physical stimulus in the eye and the subsequent neural stimulus in the brain. It seems like the former is well-researched and probably fairly accurate, but the latter is still being investigated.

 

Here's a question: can wavelength violet (like around 400-410nm) be represented by an RGB colour patch? j

 

Added: Apparently so if we take the CIE chart as an example. But is the CIE chart "brain accurate"? I don't know. If you looked at a violet patch from this chart and also looked at a monochromator violet output, how different would the colours look in your brain? This chart has of course been all mashed up by being stuffed into an sRGB/Jpg box. One measurement for Violet was (127,67,236) with more blue than red and for Magenta was (186,74,213) with amounts of red/blue closer to equal. Interesting.

 

Why is there so much cyan & green on a colour space chart like this? And so little yellow?

 

CIExy1931.jpg

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Opponent colour theory says we have 3 neural channels: one for non-colour determination of white/black/grey tones, one for red/green and one for blue/yellow.

The red/green channel changes polarity at 475 and 575 nm, the equilibrium wavelengths at which the blue/yellow channel signals either pure blue or pure yellow.

The yellow/blue channel changes polarity at 500nm, the equilibrium wavelength at which the red/green channel signals pure green.

There is no single wavelength which produces a spectral equilibrium in the yellow/blue for signaling pure red. It takes a mixture of shortwave blue and longwave red.

 

Color in Electronic Displays

Edited by Widdel & Post, 1991

 

I wonder if that is why magenta is so 'harsh' ?

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