Depth of Field in Photography

A short depth of field can be very useful when you want to isolate your object from the background, such as when taking portraits or macro photography. A large depth of field is great when you photograph landscapes and overall when you want every detail to be in focus.

Control the Depth of Field

There are three variables that affect DOF, the size of the Aperture, the distance to the object and what lens you’re using. (There is a fourth thing that affects the DOF, but that’s the size of the sensor and unless you have two cameras with different sensor sizes this isn’t something to take into account.)

As you can see in the illustration above, a lower f-number equals a shorter depth of field. A higher f-number will give you focus over a longer distance — when you’re having a hard time getting the correct focus it might be a good idea to extend your DOF by changing the aperture.

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