Cerro Castelan is one of my favorite formations in Big Bend National Park. We visit the park every summer for relaxation and a little photography. The park is so spectacular that my photography seems to win out over my husband's relaxation every time.

Cerro Castelan is a distinctive landmark that towers over the surrounding desert. The mountain is a mass of volcanic and sedimentary layers ranging in color from black to red to greenish. One side of the mountain's base, the side where this photo was taken, is covered in ancient volcanic ash or tuff. Under any light the mountain is spectacular but I wanted to try something different. I wanted to photograph Cerro Castelan and the full moon.

I started planning the shot two days in advance of the full moon by consulting my moon rise chart and the topographic map. The chart gave me the coordinates for the moon rise on the day before the full moon and the topo map was used to get a general idea of my shooting opportunities. These two tools gave me a general idea where to set-up my camera.

If you're going to include the full moon in a landscape, it's best to take your shot on the evening before the true full moon. That's the evening where the moon comes up in a light sky at the same time the sun is setting in the opposite direction. The moon is well illuminated and the sky has enough color to define features in the landscape.

We drove out to Cerro Castelan on the day of the shoot. I walked along the road and climbed on the tuff with my compass and camera trying to find the perfect shot. It turned out that the shot in my mind was not possible without walking way out into the desert. I shifted gears and decided to take the shot that the mountain was willing to give me.

We bummed around for the rest of the afternoon near Santa Elena Canyon and ate dinner at Cottonwood Campground. The temperature moved below 100 degrees an hour before sunset and clouds started to form in the sky. I began to panic that a thunder storm would roll in and obscure my moon so we headed up to Cerro Castelan so I could get ready.

I set up my camera in my preplanned spot once we got to Cerro Castelan. Clouds were forming in the east but I resisted my inclination to change positions. The sun started to set in the west and my inner voice continued to tell me that I should move to another vantage point. I resisted but was beginning to doubt if I was in the right place to get my shot. There was no moon anywhere in site and I was starting to panic.

I was turned around photographing the last colors of the setting sun when I heard, "there it is!" I turned around and saw the moon rising above the cloud bank. I set the camera on matrix meter, a +.7 ev, dialed in f22 with the camera on aperture priority. I shot. Then zoomed out a bit to place the moon on the golden third. The tuffs came into view and looked so pretty with the puffy white clouds in the sky. I shot nearly a whole roll of film, bracketing and changing the composition, as the moon rose in the sky.

As I packed my camera gear into the car that evening, I knew I had a shot I would like. But I never count my photos until they are hatched. I was thrilled with the results when I got the film back two weeks later. Velvia's color shift under low light was just want I wanted. Knowing the traits of film and good planning paid off once again.

Kathy Adams-Clark has been a professional nature photographer for five years. She started her company in 1992 and left her corporate job in 1995 to work the business full-time. Kathy markets the work of six other photographers (John & Gloria Tveten, Peter Gottschling, Larry Ditto, Greg Lasley, Bill Draker, and Glenn Hayes.) A year ago, Kathy's husband started writing a weekly nature column for the Houston Chronicle called "Wonder of Nature." She provides the research and photos for his column. In addition, she teaches nature photography in the Houston area for Leisure Learning Unlimited and local colleges. Her classes have also been offered by Houston Museum of Natural Sciences. In November, Kathy will lead a photo tour to the Amazon Basin for Voyagers International. The group will photograph an Indian market near Quito and then head to the Tiputini Biodiversity Research Station to photograph birds, reptiles and mammals.

Kathy's work has been published in many magazines including Birder's World, Bird Watcher's Digest, Birds & Blooms, Ducks Unlimited, Texas Parks & Wildlife, Texas Highways, and WOW. In addition her photography, she has been published in the New York Times, National Geographic Books, and Audubon field guides.