How Depth of Field works
Near and far limits, hyperfocal distance, and circle of confusion.
Where to find it
Tools tab Depth of Field
Summary
Calculator for depth of field: turns aperture, focal length, and focus distance into a near limit, a far limit, and the hyperfocal distance, scaled for the film format's circle of confusion.
Detail
How it works
Depth of Field (DOF) is how much of the scene in front of and behind your focus point looks acceptably sharp in the final print. This calculator turns your aperture, focal length and focus distance into a near limit, a far limit, and the hyperfocal distance.
Aperture
Smaller apertures (bigger f-numbers like f/16) give more depth of field. Wider apertures (f/1.4, f/2) give less. The wheel here mirrors the main aperture wheel so you can see DOF for the f-stop you plan to shoot.
Focal length
Wider lenses (shorter focal length) give more depth of field at the same aperture and distance. A 28mm at f/8 has far more DOF than a 200mm at f/8.
Subject distance
How far the lens is focused. The closer you focus, the shallower the depth of field gets, even at small apertures. Macro work has paper-thin DOF for this reason.
Near and far limits
These are the closest and farthest distances that will look sharp in the print. Anything inside that window is in focus, anything outside it is not.
Hyperfocal distance
Focus the lens at the hyperfocal distance and everything from half that distance to infinity will be acceptably sharp. Useful for landscapes and street work where you want maximum DOF for a given aperture.
Circle of confusion
The math depends on a tolerance called the circle of confusion, which is set automatically from your film format. 35mm uses about 0.030mm. Medium format and large format use larger values because the negative is bigger and the print is enlarged less.