[asa] RE: Yellow

You are right. The sensation of yellow (590 nm) is no different from that of a proper mixture of red (760 nm) and green (535 nm). However, there is no general rule that governs that the mixtures of two spectral lights match that of a single spectral light.

 
Moorad

________________________________

From: mrb22667@kansas.net [mailto:mrb22667@kansas.net]
Sent: Sun 11/30/2008 3:13 PM
To: Alexanian, Moorad
Cc: asa@calvin.edu
Subject: RE: Yellow

Quoting "Alexanian, Moorad" <alexanian@uncw.edu>:

>... What I am saying is that yellow is
> subjective rather than objective. Note that if that were not so, then a
> psychologist would also consider hallucinations as objective.

Speaking of yellow, the human brain actually has two distinct perceptions that
both get labeled "yellow". One is the pure wavelength of yellow light as
differentiated out by a prism or rainbow. The other is a mixture of red and
green --CRT 'yellow'-- that (fools?) our brain. Is this a form of universal
hallucination? The effect of the scrolling marquees which alternate red and
green columns is a striking display of this. You "see" a yellow message until
you focus on just one column of lights and then easily perceive that it is pure
red or pure green. I suppose all the "yellows" we see in the world could be
either pure or the mixture and could only be distinguished if one went around
with a spectroscope. Is anyone familiar with the science behind this? Or would
it be more psychology?

--Merv

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Received on Sun Nov 30 16:24:38 2008