Depth of Field Calculator

How the depth of field calculator works

Evidence photography needs the whole item and its scale acceptably sharp, which is a depth of field problem. Depth of field grows as the aperture closes, as the subject gets further away, and as focal length shortens.

Hyperfocal distance is the focus setting that puts everything from half that distance to infinity within the limits, which is useful for wide scene overviews. Stopping down past roughly f/11 on APS-C introduces diffraction softening that offsets the gain.

Frequently asked questions

What aperture should be used for evidence photography?

Enough depth of field to cover the item and its scale, commonly f/8 to f/11, balanced against diffraction. Set focus on the plane of the evidence and check both limits before shooting.

What is hyperfocal distance?

The nearest focus distance at which the far limit reaches infinity. Focusing there maximises the sharp zone for a scene overview, extending from half that distance to infinity.

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