Depth of Field

Depth of Field:

Depth of field is analogous to the area in focus of the picture. The top picture shows a long depth of field where all chess pieces are in focus. The bottom picture, only the castle is in sharpest focus and the rest are gradually falling out of focus.


There are three ways to control your depth of field:

1. F-Stop/Aperture
To create a Long Depth of Field use a large numbered aperture to make a small aperture opening (F22, F29, F32, F64). Ansel Adams used F64 to have everything from foreground to background in focus.
For a shorter depth of field, use a small aperture to create a large aperture opening (F2.8, 4, 5.6).

2. Focal point: to have everything in focus focus further away.
To blur the background, focus on something close to you.

3. Lens: using a wide angle lens or setting on your lens (18-28) will create long depth of field. Using a telephoto lens will shorten depth of field. On a zoom lens, zoom out for longer depth of field and zoom in for a shorter depth of field.

When should you use a short depth of field: Sports photography, close-ups, portraits.
When to use a long depth of field: landscapes

Depth of field will be greater behind your focal point than in front of your focal point. 2/3 of your area in focus will be behind your focal point and 1/3 of the area in focus will be in front of your focal point.

Depth of field preview: Most digital SLR cameras will have a depth of field preview button on the side of the lens (look up your camera's specific location in your manual). While you're composing your picture, push this button to get a preview of your depth of field in your view finder. The red arrow on the camera on the right shows where the depth of field preview button is on most Canon DSLRs. Below shows the depth of
field preview button on the Nikon dSLR camera bodies.

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