DEPTH OF FIELD (DoF)

A camera can only focus its lens at a single point, but there will be an area that stretches in front of and behind this focus point that still appears sharp.This zone is known as the depth of field. It’s not a fixed distance, it changes in size and can be described as either ‘shallow’ (where only a narrow zone appears sharp) or deep (where more of the picture appears sharp).

​A shallow DOF would mean that the depth of the field that is in focus is very minimal or shallow, therefore everything in front of and behind that range is out focus. This out of focus light outside the range of your DOF appears blurry or soft, often referred to as “bokeh”. The depth of field is determined by the aperture of the lens being used. 

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.