Thursday 13 August 2009

Crystal Clear

The night sky was crystal clear and all the stars were out. it was absolutely beautiful. i could see my breath. it was colder than we had been used to. There was a definite chill in the air. Sweat ran down the side of my face and I started to shiver.
Eyes take a long time to adjust in darkness. The cones in your eyes enable you to see in the daytime, giving colour and perception. But theyre no good at night. What takes over then are the rods on the egde of your irises. They are angled at 45 degrees because of the convex shape of the eye, so if you look straight at something at night you dont really see it, its a haze. you have to look above it or around it so you can line up these rods, which then will give you a picture. it takes 45 minutes or so for them to become fully effective, but you start to see better after 5. And what you see at first and what you see five minutes later are two very different things.

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