A wide aperture typically produces which effect on depth of field?

• A. Shallow depth of field
• B. Deep depth of field
• C. No depth of field
• D. Infinite depth of field

Answer: (A)

A wide aperture creates shallow depth of field because opening the lens to a larger size narrows the zone of sharp focus. Depth of field is the range of distances that appear acceptably sharp in an image. When the aperture is wide, more light comes through, and the circle of confusion for points not exactly on the focus plane grows larger, so only a small range around the focus point stays sharp. This produces a crisp subject with a blurred background and foreground. If you stop the lens down to a smaller aperture, more of the scene falls within the sharp range, increasing depth of field.