A short depth of field is focused in the foreground, but is out of focus in the immediate background. There is no middle-ground. The aperture is wide open, an f/stop of 1.4, 2.8, or 4

A medium depth of field gradually has less focus as it recedes to the background. There is a definite foreground, mid and background visible. A f/stop of 8 or 11

A long depth of field is equally sharp focus from front to back. This would be an f/stop of 22, 16.

a wide angle lens (28mm) has a long depth of field, and is appropriate for creating a more spacious view for interiors or even landscapes. This lens has a wide angle of view.

An example of a telephoto lens. 200 mm lens has a narrow angle of view, helps you see far away.

                                                               

A telephoto lens will decrease the depth of field (short depth of field).

Depth of field is also affected by distance. Typically the closer to your subject your lens is, the less depth of field you will have (short depth of field).

The further your subject is from your lens, the greater the depth of field becomes

The three factors that affect depth of field

1. Size of lens aperture

2. Type of lens selection

3. Distance of subject to lens

A mirror lens is a cheap alternative to telephoto lens, but can only be used in bright light, and you cannot achieve a long depth of field with it. The lens uses two reflective mirrors instead of ground glass to “focus”.

                                                 

     

$6,700.00 for an ultra-fast lens, capable of taking pictures in extremely dim lighting. Has a very wide aperture.

Fish eye lenses create a very unique wide angle view, with a long depth of field all around.

A fish eye lens is very short.