Choosing which format to use is a very important part of composition. Try it both ways. View the scene in both formats, see which one looks better. But more importantly, there are several guidelines to keep in mind when deciding which format to use. Below are several guidelines to follow and the when and why's of using each one. Study the examples and try to apply the guidelines to your own work.

The frame shape should always match the shape of the subject. For instance, if shooting a skyline scene, the only choice is horizontal. Why? Because a skyline is horizontal, it follows the horizon. On the other hand, if the subject is a skyscraper, the choice would be vertical. Why? Because skyscrapers are vertical buildings. The shape of the frame isolates the subject. Compositions should not look like a round peg shoved into a square hole. The frame should compliment, not distract from, the total composition. Should this rule of thumb ever be broken? Of course, but only if you have a very good reason for doing so and only if the frame choice adds to the theme.

Take a look at the three images of the roses. In the first photo, the photographer has chosen to place a rose dead center of the frame. Why? There seems to be no valid reason for this placement and two-thirds of the space is wasted. The subject is a single rose. Flowers with long stems are naturally vertical in shape. Then why place it into a horizontal frame? Why place it dead center? Look at the second image of the same flower. The change is in the format, here the flower itself is the subject and the viewers know it immediately because the wasted space is gone. Now look at the last image of the roses. This composition works? Why? Because here the subject is not a single rose, but rather a group of roses in a horizontal arrangement. The repetition is carried out through all three thirds of the image. The repetition is the subject or theme, not the single rose. A single rose is vertical where as a bed of roses is horizontal. The choice of format emphasizes the subject and reinforces the theme.

Look at the three photos below. Because of the placement of the bird in the frame as well as the format, each one tells a different story. In the first one, the bird itself is the subject. The frame matches the shape of the bird. In the second photo, there seems to be no direct relationship to the shape of the bird and the photographer's choice of frame shape. The poor bird seems squashed into the frame. The only relative theme here maybe to show the bird's habitat. In that case, the bird is not the subject, the habitat is the subject. In the third image, the bird is again the subject but the theme has changed. Is the bird ready to fly away? Has it sensed the photographer's presence? We don't know, but because of the placement in the frame we can assume that the photographer used a horizontal format and left one-third of the frame blank for a very good reason.

It is important to pay attention to the shape of the actual subject when choosing the frame shape. Not only will your shots look better, they will start to look more professional.