We get a good composition when the right combination of subject matter and light coalesces in the viewfinder. Subjects are often moving. Light is often changing. We need to be thinking ahead to avoid missing shots.
Here's a photograph I would never have taken if I hadn't been thinking ahead:
I left home well before dawn that day, headed for a picturesque creek in Arizona's Verde Valley. As I was driving north, I noticed the full moon sinking in the west. It occurred to me that the moon might be close to the horizon and ripe for a photograph at about the same time the sun was rising. I started to visualize a photograph along these lines. I had no idea, though, what would be in the foreground.
I know the area that I was driving through quite well. As I thought about the alternatives, I decided to take the road that led to the area where this shot was taken. I was searching for a foreground. I wasn't expecting the Taj Mahal or Angelina Jolie to materialize—I just wanted something that would look interesting when illuminated by the rising sun. The sun was about to rise when I got to this spot. I saw the two low hills and stopped the Jeep. I knew that I'd want the telephoto lens for the moon to be large enough. A wide-angle lens would turn the moon into a pinprick. I hurriedly set up the tripod, changed lenses and made my adjustments just as the sun rose. I was almost too late. The first rays of sun lit up the hills just as I was getting set. I took several exposures. This was the best of them.
In a sense, this photograph resulted from my being in the right place at the right time. Being there, however, did not result entirely from luck or from inspiration. It resulted from having learned to think about what was going to happen to potential elements in a photograph—in this case, that the moon would be low and the sun would be rising at about the same time, and that a dramatic effect might result. I visualized most of a photograph that wasn't yet available—but soon might be. Then I put myself in the position to capture it.
Some photographers go to great lengths to foresee an opportunity for a photograph. Craig Varjabedian is a New Mexico photographer whose work I admire. In his book Four and Twenty Photographs, Varjabedian recounts how he took a particular photograph of the moon above a particular site. He consulted data on the moon's paths, and concluded that the conditions would be right for the photograph he wanted on November 21st, at 5:00 PM. The fine photograph that resulted justified such detailed planning.
Here's a somewhat different example of anticipating a photograph. Not long ago I was at the local zoo. I arrived at the rhinoceros exhibit just as the animals were emerging to feed. The rhinos' keeper sneezed twice in quick succession. It was obvious that her sneezes startled the animals. "Sorry, guys," she said. It occurred to me that I'd never heard anyone apologize to a rhino before.
Anyway, it was early morning and the rhinoceros' enclosure was mostly in shadow. There was, however, one sunlit spot between me and one rhinoceros. I noticed him heading for the sunlit spot. Luckily, rhinos are fairly slow. I quickly spot-metered the sunlit spot, adjusted the exposure and then took this photograph when the rhinoceros walked into the light.
Anticipating the route of the rhinoceros wasn't hard. I just had to be thinking about it. I also had to visualize the potential photograph well enough to opt for a low-key, "underexposed" approach, and to set the exposure accordingly.
I took the photograph of the moon when I'd set out to photograph a creek. I took the photograph of the rhinoceros when I'd gone to the zoo to photograph the Sumatran tiger. The best photographs from an outing often aren't the ones I'd planned to take. Once, years ago, I told my wife that I was going to the mall to buy some slacks. I came home with a banjo instead. When taking photographs, I often come home with a banjo.
But I digress. Being able to think ahead comes from learning and practice. When I got serious about learning photography, I read books about composition. Several recommended anticipating changes in subject matter and lighting. That made sense. When I was out with a camera, though, I didn't seem to do it very much or very well.
Gradually, though, I learned to do it. I would remind myself to be alert to how compositional elements might move or the light might change, as the books had suggested. I saw that a cloud passing in front of the sun could change hard light to diffuse light, for better or worse. I learned that a sudden break in cloud cover could produce a very dramatic lighting effect. I learned to keep an eye on the sky, so that I could anticipate such changes. In time, staying alert for how subjects and light might change became more of a mental habit.
When I'm planning an outing for landscape photography, I always check the detailed weather forecast in advance. What I'm mainly interested in is the expected amount of cloud cover for each hour. There are some places I won't bother to photograph without some cloud cover. Other places are fine with a clear sky. At times, reading the forecast has caused me to change my destination.
Learning to think ahead is an ongoing process. It's like learning to play the banjo, except that it's much less painful to others. With some frequency, I still get blindsided by a terrific opportunity for a photograph that comes and goes before I can react. With practice, though, I'm getting more of those shots.
You can see more of Don Peters' work here.