Calculate thin-lens near/far focus limits and hyperfocal distance from actual focal length, focus distance, f-number, and an entered CoC criterion.
A quick decision brief for this specific tool
Actual focal length, taking f-number, focus distance from the lens/camera reference plane and an explicit acceptable circle-of-confusion criterion
Thin-lens hyperfocal distance, near/far limits, front/rear depth and finite or infinity state
Use exact thin-lens hyperfocal and near/far equations with all lengths converted to the same unit
Choose your path
Calculate auditable thin-lens depth-of-field geometry from an explicit acceptable-blur criterion without assigning sensor presets or promising perceived sharpness.
See when the far entered-criterion limit reaches infinity without using a symmetric approximation.
Enter actual focal length, aperture, focus distance and the chosen output CoC.
Gets exact near/far and hyperfocal values with infinity handled explicitly.
Record front and rear acceptable-focus geometry around a measured mark.
Use the lens-plane focus distance and production-approved CoC criterion.
Gets transparent geometry while retaining lens tests, movement and viewing criteria.
Know when the ordinary thin-lens model is insufficient.
Compare focus distance to focal length and read the close-focus/magnification boundary.
Does not mistake a geometric estimate for measured macro sharpness.
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
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Circle of confusion is an input criterion, not a measured sharpness result. Choose it for the intended image area, enlargement, viewing conditions, and acceptance standard; the calculator does not prescribe a sensor-format value.
c = user-entered acceptable circle diameter in mmAll lengths are converted to the same unit. The far limit becomes infinity when its denominator is zero or negative; finite near and far limits are not assumed to be symmetric around the focus distance.
H = f²/(Nc)+f; Dn = Hs/(H+s−f); Df = Hs/(H−s+f)The output is geometric. Real results can differ because of lens extension at close focus, magnification, diffraction, aberrations, focus shift, field curvature, camera or subject movement, processing, enlargement, and viewing conditions.
Calculated geometry ≠ measured lens/output sharpnessUpdated: August 2026
Enter the actual focal length, taking aperture, measured focus distance, and the CoC criterion approved for the output. Confirm when the calculated far limit reaches infinity, then test the real lens and foreground detail.
Use distances from the camera or lens reference plane and a production-defined criterion. Record asymmetric front and rear limits, then retain movement, lens tests, monitor/output, and focus-puller judgment outside the arithmetic.
If focus distance approaches focal length, the engine rejects the invalid geometry. At meaningful magnification, use a lens- or magnification-aware model and physical testing rather than treating this ordinary thin-lens result as decisive.
Document the actual output and acceptance criterion. A format preset can hide enlargement, crop, display/print, viewing-distance, and audience assumptions.
Depth of field is criterion-based and transitions gradually. Verify the real lens, capture stability, focus accuracy, processing, enlargement, and viewing conditions.
This calculator records thin-lens depth-of-field geometry at the circle-of-confusion criterion you enter. It does not assign a criterion from a camera label or promise that the calculated zone will look sharp in every lens, capture, output, and viewing condition.