Focus; Autofocus - Nikon D750 User Manual

Focus

This section describes the focus options available when
photographs are framed in the viewfinder. Focus can be
adjusted automatically (see below) or manually (0 132). The
user can also select the focus point for automatic or manual
focus (0 127) or use focus lock to focus to recompose
photographs after focusing (0 129).

Autofocus

To use autofocus, rotate the
Focus-mode selector
focus-mode selector to AF.
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