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.

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 find it some of the hardest photography and the most challenging photography I've ever done. It's a real challenge to work with the natural features and the natural light.

If we limit our vision to the real world, we will forever be fighting on the minus side of things, working only too make our photographs equal to what we see out there, but no better.

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

The most interesting parts of the natural world are the edges, places where ocean meets land, meadow meets forest, timberline touches the heights.

Today, I'm very careful not to mention very specific locations when I write or give captions.