Depth of field (DOF) deals with how much of a picture is sharp in front and back of when you attend to the main subject. How to control Depth of field (DOF) is mainly depended by aperture size though other factors come into play including the focal distance of the lens and the space the background is from the subject.
Photographers may consciously control depth of field for artistic designs, aiming to achieve attractive background blur known as bokeh. For example, a shallow depth of field is usually used when taking close up.
(Read Article : Obtain Camera for Maximum Bokeh )
More (deep) Depth of Field
The further away your camera is from the subject, the greater the depth of field.
Higher f-stop numbers obtained by using small scale apertures create deep depth of field. Short focal length, as well as each time a lens is set at wide angle, help increase depth of field.
Less (shallow) Depth of Field
Lower f-stops (larger apertures) decrease DOF. Long focal length (zooming in) produce less DOF.
You can also create the background look out of focus by placing the subject close to the camera and having the background far away.
If you cannot manually control aperture, use Portrait style for shallow depth of field. For deep depth of field, use Landscape or Infinity mode.
How to control Depth of Field Video Tutorial