Focus Bracketing
An in-camera function that automatically shoots a sequence of frames at incrementally different focus distances.
Measured in
count
In depth
The photographer sets the number of frames and the step size, focuses on the nearest point, and the camera works away from the lens. Choosing the step is the skill: too large leaves unsharp bands between frames, too small wastes hundreds of exposures. Some cameras also perform the stack internally rather than requiring desktop software.
Examples in practice
Setting 60 frames at step 4 on a macro lens covers a two-centimetre subject with comfortable overlap.