I think one of the most common photographic challenges all of us face is this -- we see subjects and the camera sees light. What happens is that we can see a detail in a huge range of light from bright sun to dark shadows. In addition, we can see really dark things next to really bright things because we quickly change our focus as our eyes scan the areas. The camera simply cannot do this. The camera is restricted by its limitations on seeing a range of brightness.
In addition, the camera really emphasizes the light on the subject and scene, more than our eyes do. We have to force ourselves to see the light the way the camera does. All of the photographs here are from my trip to the redwoods last month. Conditions then were challenging because the light was always strong in contrast when we were there. Sometimes you would just try to force a composition based on the subject, but the light would not cooperate, such as this scene.
Another reason for this difference is that we focus both our eyes and our attention on individual parts of a scene as we look at it. If you look at a sunlit flower in front of a dark-shadowed tree, you will see both well, not just because of the ability of our eyes to dig detail out of both areas, but also because we mentally focus on parts of a scene. We look at the flower and focus on the flower, making it show up clearly in our mind. We look at the tree and focus on the tree, making it clear in our heads. We are not conscious of doing this, yet we do it all the time. The camera doesn't do that. It simply shows us everything at once, the entire scene, the flower and the tree at once, without any focus to make them clearer. This then presents the scene in a visually "flat" (meaning unemphasized or not defined) way.
What often happens is that light emphasizes the wrong things in a scene. I have seen all sorts of challenges from this in my classes, such as a really nice photograph of an animal (the photographer saw the subject just fine) but the light emphasizes the rump of the animal rather than the head. Or a lovely scene of woods with a trail winding through it (the photographer saw that subject well), but the light emphasizes the pattern of the trees and a lot of spots of light across the ground. Or a what could be an excellent composition of a stream rushing down the side of a mountain with a small waterfall, but the light emphasizes the wrong parts of the stream and a scrubby bit of a stump beside it. Or in the next photo of a nice group of ferns with a redwood, but the background gets the attention because of the light.
Composition is not simply about what is enclosed within the frame of a photograph and how it is arranged there. It is also about emphasis and how light changes that emphasis.
There are two good ways to help combat this tendency. First is to use your LCD. I set my LCD for the maximum Review time because the default is usually way too short (it is a carryover from the days of poor battery performance). That way, when I shoot something, I instantly get a review image on my monitor that will help me confirm I was looking at the light and not just the subject.
Second is to go out and photograph light. I spent a lot of time doing that years ago, but even today, I will see some interesting light and photograph it just to see what it looks like when photographed. This means literally looking for interesting light to photograph, not subjects. Try going out for an afternoon and just photographing light. You may never feel any of the resulting shots are worthy of printing out and putting on the wall, but I guarantee you will learn a lot about seeing light. The following photo is as much about light as it is about some ferns.
I just developed a new course for BetterPhoto.com called A Darkroom Called Lightroom. I have long wanted to do this, and the course includes how-to videos to show exactly how to do the work in Lightroom. This is truly about darkroom work, not digital effects, not computer work, but about using the ideas and philosophy of working on an image that darkroom workers like Ansel Adams, W. Eugene Smith, and so many other traditional darkroom photographers used. This is about enhancing and enriching the core image, just as Ansel Adams worked a negative for a final print. The 4-week class starts in August and will repeat each month.
Also, my friend and really excellent photographer, Ian Shive, just got a terrific award from the Sierra Club. He is the 2011 winner of the Ansel Adams award for conservation photography. Ian has a wonderful book on the national parks and has done a lot for them. He definitely deserves this recognition.