Selective Focus

One of the major benefits of photography is the ability to achieve images with amazing sharpness and clarity. With current 35mm cameras and film one can easily read the cover of the NY Times from a photograph of the entire page. However, just because that amount of sharpness is attainable doesn't necessarily mean that everything within the picture area should be razor sharp. This is up to the artistic interpretation of the individual photographer.

With a good understanding of the concept of depth of field, a photographer has the ability to intentionally place certain areas of the photograph out of focus. By doing this it is easier to direct the viewer's attention to the area within the photograph that is most important. It also presents a tool to the photographer that will allow the illusion of three dimensions to be achieved. If while photographing overlapping subjects one intentionally chooses to make the subject in the foreground or the one in the background out of focus an illusion of three dimensions occurs.

Depth of field is effected by three things: the size of the lens opening, the focal length of the lens, and the distance from the camera to the subject. The larger the f-number the greater the depth of field. The shorter the focal length the greater the depth of field. The greater the distance from the camera to the subject the greater the depth of field.

Assignment: Pick out a scene that has both foreground and background subjects. Take a series of photographs with very shallow depth of field, each photograph should have a different object within the scene in sharp focus. Then go through the same exercise with a moderate depth of field and again with a large depth of field. View the images and see for yourself the difference in the appearance. Utilize what has been learned in this assignment to control the viewer's attention and create the illusion of three dimensions.