A shallow depth of field in photography and videography is when your subject is in focus and your background is out of focus. It is a technique used to bring the viewer's attention to your subject.

DOF stands for depth of field. There are three main factors:

  • Distance to the Subject
  • Aperture
  • Focal Length

 

A shallow depth can be achieved by the following...

  1. Shorten your distance to the Subject
    dof distance 
  2. Open your aperture as wide as you can. (Use a small "F stop").
    dof aperture 
  3. Use a lens with a larger focal length - or if you are using a telliphoto zoom lens, zoom in. However, to fit the frame nicely with a large focal length lens, your subject may have to stand further away - which defeats this method (see Method 1).
    focal length 

This video explains the concepts.

 

Thanks to Dylan Bennett and Ling talfi for the illustrations.