You may have heard the term depth of field (DoF), but if you are new to photography you may not yet be taking advantage of how DoF can enhance your photos.
A basic definition of depth of field is: the zone of acceptable sharpness within a photo that will appear in focus. In every picture there is a certain area of your image in front of, and behind the subject that will appear in focus.
This zone will vary from photo to photo. Some images may have very small zones of focus which is called shallow depth of field.
Three main factors that will affect how you control the depth of field of your images are: aperture (f-stop), distance from the subject to the camera, and focal length of the lens on your camera. Here are some explanations and answers to other common questions concerning depth of field.
How does aperture control depth of field?
Aperture refers to the access given to light from the lens to the camera sensors. The size of your aperture (the diameter of the hole through which light enters the camera) controls the amount of light entering your lens. Using the aperture (f-stop) of your lens is the simplest way to control your depth of field as you set up your shot.
Large aperture = Small f-number = Shallow (small) depth of field
Small aperture = Larger f-number = Deeper (larger) depth of field
It may be easier to remember this simple concept: The lower your f-number, the smaller your depth of field. Likewise, the higher your f-number, the larger your depth of field. For example, using a setting of f/2.8 will produce a very shallow depth of field while f/11 will produce a deeper DoF.