Taking a Portrait With a Shallow Depth of Field
Tips and Tricks From a Professional Photographer
Apr 9, 2009
Professional photographers control the depth of field in a photograph to isolate a subject who is photographed against a busy background. Two things affect the depth of field in a photograph. The first is the camera's aperture. The second is the focal length of the lens.
Setting the Aperture
The primary setting that will allow control of depth of field is the camera’s aperture. All digital SLR (DSLR) cameras allow aperture control. Some point and shoot digital cameras also allow the aperture to be manually set. Aperture is used to control the amount of light passing through a lens. Larger apertures create a more shallow depth of field.
When the depth of field is shallower, the background blurs more. Smaller aperture numbers correspond to larger openings in the lens. For example, a setting of f/2.4 sets a larger lens opening than f/22. The depth of field is shallower in photographs taken at f/2.4 than at f/22.
Setting the Focal Length
The other setting that will affect depth of field is lens focal length. Longer focal length lenses, or telephoto lenses, create shallower depth of field. If your camera has a lens that ranges from 18mm to 130mm, the depth of field will be shallower at 130mm. Some point and shoot cameras don’t display focal lengths. The depth of field is shallower at the telephoto end of the range than at the wide angle range.
Taking the Portrait
To take a portrait with a shallow depth of field, set the aperture to the largest available. On DSLRs and point and shoot cameras that support it, the best way is to set your camera to Aperture Priority. Aperture Priority will automatically set the shutter speed for the correct exposure.
Once the aperture has been set to the smallest number, which corresponds to the largest lens opening, set the lens to its longest focal length. The focal length is either set by twisting or pulling the lens barrel on many DSLR lenses or by pressing the plus (+) button on all point and shoots and some DSLRs.
Frame the subject in the viewfinder and focus on the eyes. If the subject’s face appears too large in the viewfinder, back up until the face is properly framed. Once the subject is properly framed and focused, press the shutter release. The background of the photograph should be pleasingly blurred out making the subject stand out in the portrait.
