Re: [Phys-l] An Unsolved Color Problem

[Bernard Cleyet <bernardcleyet@redshift.com>]

The Exploratorium people are experts on this question.  A sig. part of 
the floor is devoted to sight.  I'm too lazy to find an appropriate 
page;  here's a beginning:


http://www.exploratorium.edu/seeing/about/introduction.html


bc

more:

http://www.exploratorium.edu/seeing/links.html

John Denker wrote:

> On 07/17/2007 08:08 AM, Polvani, Donald G. wrote:
>  
>
> > Here is the Astronomy Picture of the Day (APOD) for today July 17,2007.
> >
> > http://antwrp.gsfc.nasa.gov/apod/astropix.html
> >
> > I haven't "solved" the problem of how the two squares can appear to have
> > different colors and yet be the same color,
> >    
>
>
> The human eye is not a spectrophotometer!
>
> Yeah, I know every grade-school science book implies that the eye
> just responds to the colors of the incoming light, pixel by pixel
> ... but it just ain't true.  Not even close.
>
> There's no reason why it should be true.  Given a few million years
> of primate evolution, you would expect the eye to evolve to so that
> it can see the difference between ripe fruit and unripe fruit, and
> see the difference between the tiger and the tall grass.  Doing a
> good job of this requires _color constancy_ ... where color refers 
> to the inherent pigmentation of /objects/ in the field of view and 
> requires _discounting the illuminant_ because the illuminant is 
> certainly not inherent to the objects, and because the illuminant 
> changes wildly from situation to situation.
>
> http://en.wikipedia.org/wiki/Color_constancy
>
> _______________________________________________
> Forum for Physics Educators
> Phys-l@carnot.physics.buffalo.edu
> https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
>
>
>