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Grassblade wrote:
> That's a pretty cool picture.
> The black background conspires with the dark blue to make the red much more
> apparent. Pick a lighter background colour like a neutral gray, or go all
> the way to white.
> Colour-wise, <0.0784, 0.1706, 1.0000> is somewhat different from <1.0000,
> 0.1706, 0.0784>, I mean, apart from the obvious hue change. In The Gimp the
> red <255,40,20> looks significantly brigther to me than the blue <20,40,255>
> (I obtained these values by multiplying your colour vector by 256). It could
> be just monitor settings, though. :p
> 
	It's not just your monitor settings: perceptually, the same value
is significantly darker if it's blue than red (and green is the
brightest). When computing the equivalent brightness for a colour,
you should use the following coefficients:

In the Gimp on a PC (Macs have different values):
brightness = blue * 0.11 + green * 0.54 + red * 0.35

In Povray the coefficients should be gamma corrected:
brightness = blue * 0.02 + green * 0.71 + red * 0.27

		Jerome
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