On Sep 21, 5:21*am, "Lord Androcles, Zeroth Earl of Medway"
wrote:
"Paul Ciszek" wrote in ...

My camera has a choice of "white balance" settings. *If I use "Sunlight"
on the assumption that the moon is a sunlight landscape, photos of the
moon come out looking a little brownish. *If I use "Auto", the moon
appears nearly colorless. *The former coloration is not implausible,
but which is closer to the truth?

Fortunately, I can make this decision retroactively for photos shot
in RAW mode.

--

Colour is subjective and dependent on surrounding colour, as
this image clearly shows.
* *http://androcles01.pwp.blueyonder.co...e/illusion.JPG

Orange and brown are the same color but with different saturations.

This is a better illusion where blue and yellow are compared:

http://lesswrong.com/lw/290/blue_and...inted_choices/

The phenomenon that leads to the illusion is called lateral
inhibition. Rods and cones that receive, for example, green light
send signals to adjoining rods and cones to respond less strongly to
green light. This tends to increase perceived contrast and enhances
the ability to distinguish slightly differing colors.