Composition: Framing

Placing a frame around the center of interest of an image can be a very effective way of improving an image. The frame serves to help define the center of interest, add depth to an image, and lead the viewer's eye.

Define: When used properly, the frame provides details that help to define the center of interest. Essentially, the frame puts the center of interest into context by showing some of the environment in which the center of interest exists.

Depth: The frame provides a foreground that adds depth to an image.

Lead: The frame also serves to lead the viewer's eye to the center of interest. The frame essentially focuses the attention.

-Ron Bigelow

I might add that framing is also useful for scenic or city shots when the gray skies add nothing to the photo. Here are two websites with examples: