Depth of Field Calculator
Calculate the depth of field, near and far limits, and hyperfocal distance for any camera, lens, and aperture combination.
I check depth of field numbers when planning portrait setups or any shot where I need to be confident about what is sharp and what is not. Shooting at f/1.8 at 10 feet with an 85mm lens on full frame: depth of field is about 10 inches. One step back or forward, and your subject's eyes can shift in or out of focus. Understanding these numbers before the shot removes guesswork.
Depth of field is shallower with: longer focal lengths, wider apertures (lower f-number), and shorter subject distances. The shallowest DOF in common portrait work is a long lens at wide aperture close up. The deepest DOF is a wide lens stopped down at distance.
Circle of confusion
Depth of field calculations are based on the circle of confusion (CoC), the maximum size a point of light can be on the sensor before it appears unsharp to the human eye at typical viewing distances. The CoC depends on sensor size, print size, and viewing distance. Larger sensors have larger CoC values, producing less apparent depth of field at the same f-stop and focal length. This is why full-frame cameras produce shallower depth of field than crop sensors at equivalent field of view.
Hyperfocal distance
The hyperfocal distance is the closest focus point at which everything from half that distance to infinity appears acceptably sharp. Focusing at the hyperfocal distance maximizes depth of field for a given aperture and focal length. Landscape photographers use hyperfocal focusing to ensure foreground-to-infinity sharpness without stopping down excessively.
The crop factor effect
A 50mm lens on an APS-C camera (1.5x crop) has the field of view of a 75mm lens on full frame, but the depth of field of a 50mm lens. To match both the field of view and depth of field of a full-frame 85mm f/1.8, you would need an APS-C lens of about 56mm at f/1.2. This is why photographers who want very shallow depth of field often prefer full-frame systems.
Frequently asked questions
Why does the calculator show "infinity" for the far focus limit?
When you are focused at or beyond the hyperfocal distance, everything from the near focus limit to infinity is within the depth of field. This is common with wide lenses stopped down, or with any lens focused far away.
How much depth of field do I need for portraits?
For head-and-shoulders portraits, 4-8 inches of depth of field is usually sufficient to keep eyes, nose, and ears sharp while blurring the background. For full-length portraits, 12-24 inches is more appropriate. For group photos where subjects are at different distances, f/5.6-f/8 is usually safer than wide open.