skiing

this past monday i had a ton of fun skiing with my friends in hidden valley. my only complaint is that at the time they were making snow. this is really annoying because when you are speeding down the hill and the falling snow hits your cold face it really hurt. the only way to stop the pain is to wear goggles. my goggles happen to have not been clear. they were a little tinted. (this is useful for when it is sunny.) one interesting thing i noticed was that after some time, even though the goggles were shaded, everything looked perfectly clear as if i was not wearing the tinted goggles at all. at first i thought it was because of sensory adaptation but then i remembered that we learned that our eyes do not adapt in the same way as our other senses so i wondered why everything looked normal. that night it hit me. COLOR CONSTANCY!!!!! that was the solution to all my problems. our brain calculate the average illumination conditions of a scene and then subtrack those conditions. so when i put the goggles on everything looked blueish but then my eyes subtract blue from everything so that color will remain constant of what i know it to be. color constancy is the reason why a blue object will look blue no matter what light you look at it under. color constancy is responsible for a really cool trick that i dont think we mentioned in class called the land effect.  (take a look at the link below)
http://www.grand-illusions.com/acatalog/Land_Effect.html
the land effect is basically a picture that only contains one color but because of how our vision works we subtract that main color and we can see other colors as well. it is really cool.
the picture in the link is only red but it looks like it contains other colors as well.
when i take my goggles off i experience another phenomena we talked about in class the opponent process theory. since my blue cones kept on firing over and over when i took the goggles off all the yellow rushed in and everything looked a shade closer to yellow (just like we had experienced in class).