Depth of field

Depth of field 

depth of field calculator

Depth of field is the range of distance that appears is focus or blurred in a photograph. We define depth of field as the zone of sharpest focus in front of, behind, and around the subject a lens is focused on a specific subject. With TTL (through the lens) SLR camera, DOF can be previewed in the viewfinder of a camera - the preview is very handy for critical type of work. For an example, when taking a product shot, when you require absolute certain if DOF is adequate to cover the object you intend to photograph Generally, the closer the subject to the camera, the more evenly with the distribution of depth of field in front and behind the subject. As distance of focus extends, DOF usually will be more behind than in front of the focused area.

This photo shows narrow depth of field, this means that things in the foreground are in focus and things in the background are out out focus or blurred. 

This is wide depth of field as everything in the photo is in focus, this is achieved by using a small aperture and long shutter speeds. This means that you most likely would have to use a tripod, wide DOF is mainly used for landscape photography.

• The closer the object is to the camera, the more shallow the depth of field you'll get.
• The longer the focal length, it'll give more shallow the depth of field.
• The larger the aperture (smaller the F-number), the more shallow the depth of field.

It is important to understand how to affect the depth of field in order to use it in image composition. Shallow depth of field is usually used in portraits and large depth of field is usually used in landscape photos.