Back-button focusing basics

Back-button focus moves autofocus activation away from the shutter button to a button on the rear of the camera. The shutter button can then take the photograph without necessarily refocusing.

Why photographers use it

It can be useful when you want to focus once and take several photographs without the camera refocusing each time, or when tracking movement with continuous autofocus. It is a workflow preference, not a technique that automatically improves sharpness.

Do not change it just because others do

If half-press shutter focusing works well for you, there is no need to change. If you try back-button focus, check your manual because button names and custom-control menus vary widely between cameras.

Try it for yourself