My first thought is always of light.

When the light is right and everything is working for me, I feel as tense as when making a difficult maneuver high on a mountain. A minute - and sometimes mere seconds - can make the difference between a superb image and a mundane one.

I began taking pictures in the natural world to be able to show people what I was experiencing when I climbed and explored in Yosemite in the High Sierra.

I think that cognitive scientists would support the view that our visual system does not directly represent what is out there in the world and that our brain constructs a lot of the imagery that we believe we are seeing.

You only get one sunrise and one sunset a day, and you only get so many days on the planet. A good photographer does the math and doesn't waste either.

Small, portable digital cameras that exceed the performance of an off-the-shelf Nikon using 35mm slide film are further away from current reality than the proposed NASA manned Mars mission, although I expect both to happen sometime during my lifetime.

And most of my early pictures failed but about one in a 100 somehow looked better than what I saw.