Another rant about composition. It is amazing how many images I am seeing recently with subjects dead center, for no good reason. There are reasons for centered composition, most notably symmetrical compositions, and most of those usually sit high or low rather than perfectly in the middle of the frame. The images I refer to have no such justification.
When you point a camera at a subject the natural inclination of the photographer is to put the subject in the middle of the frame. That is where the primary focusing aid usually is located, and when you look into a camera you look at the center of the framed image. However, this is something you need to train yourself to stop doing. You need to consider the entire frame of the camera and compose the subject to sit comfortably in the composition it creates. The most common place puts the visual weight of the subject at a primary compositional balance point, and the most common of those is defined by the rule of thirds. There are other “rules” you can use to learn to compose, but ultimately you need to learn to feel where the subjects in an image sit comfortably and what makes a better photograph.
By example, notice that the train in the image above is not centered but has “room to move” into the composition by sitting off center to the right and slightly higher than center vertically. There is a full article on learning composition on my Learning Page which is easily accessed by a link under my name at the top of this page. If you are a beginner or not sure exactly what I am talking about I suggest you read the article which introduces you to the language of composition and illustrates some of the guidelines you can use to help you get a feeling for better images.
Most versions of Photoshop and Elements include the rule of thirds overlay as an option in the crop tool. CS6 and Lightroom 4 include other overlay options as well. They are there to assist you in placement of the subject within the frame, but ultimately you are the final arbiter of placement. Whether you are making images for competition or just casual shots for yourself, you will discover that your results are much more satisfying if you learn to balance your subjects within the entire frame and eliminate the static feeling of a centered “bullseye” composition.