Depth of Field Calculator

Sensor mark (S). The ⦵ symbol on the top of the camera body marks the sensor plane. Lens specifications measure the minimum focus distance from it, and it is the easiest point to measure from on a PhotoRobot setup with a tape.

Lens (u). Depth of field formulas need the distance from the lens's optical center to the subject. When you pick Sensor mark, the calculator splits S into u + v with the thin-lens equation 1/u + 1/v = 1/f: u = S/2 · (1 + √(1 − 4f/S)). Near and far limits and the hyperfocal distance are then shown from the sensor mark as well.

The difference matters at product distances: a 105 mm lens at f/16 with the sensor mark 918 mm from the subject gives 4.8 cm of depth of field. Entering the same 918 mm as a distance from the lens would show 6.5 cm, about a third too much.

The conversion assumes a thin lens. Real lenses focus internally and their optical center is not exactly where the diagram shows it, so treat results close to the minimum focus distance (macro) as estimates. A thin lens cannot focus closer than 4 × the focal length from the sensor (1:1). If you measured from the front of the lens, add the sensor mark to front of lens length to get S.

Hyperfocal distance (H) is the closest distance at which a lens can be focused while still keeping objects at infinity acceptably sharp. Focus exactly on H and depth of field stretches from H/2 all the way to ∞ — the trick landscape photographers use to keep both the foreground and the horizon sharp.

For studio and product photography it's mostly an indicator: as long as your subject distance is far smaller than H (which it usually is — H grows with focal length squared and shrinks only with aperture), DoF stays symmetric-ish around the subject. When the subject distance approaches H, the far limit runs to infinity and the calculator will show ∞.

Practical takeaway for product/jewelry work: focus on the front-most detail you need sharp and use the "Near limit" / "Far limit" rows above (or the Depth of Field Chart) to confirm the rest of the object fits inside DoF.