I took this shot down in Chinatown last summer. The first photo is uncropped, while the second one has been cropped to a 1 x 1 frame, which is basically the frame size commonly used with medium format cameras. Personally, I feel the second image works best. The reason is that the man and his bike are not centred and instead the composition uses the rule of thirds. What’s that, you ask? If I were to divide the frame into three equally spaced columns I’d end up with two vertical division lines in the photo, right? Now, if I then divided the frame into three equally spaced rows, I’d end up with two horizontal division lines, right? The photo would be divided into nine squares. However, there would be four points where the vertical and horizontal lines intersected in the photo. You can draw this on a piece of paper to get the idea, if you like. Well, when composing a scene, it’s common to try to place your subject into one of those intersections, like I have in the second shot. If you look at any of the portraits I’ve done, and think about the rule of thirds, you’ll often notice my subject’s eye lines up with one of the two upper intersections. That’s not by accident.
Anyway, if it’s a tad confusing, please forgive me. It’s late and I’m tired. Here’s a link to a better explanation. Next time you’re out shooting, even with your iPhone, think about the rule of thirds when composing the shot. Better yet, try centring your subject in the first shot and then recompose and apply the rule of thirds to the second shot and see which is more pleasing to the eye.