Nikon Z 7 Reference Manual page 67

6
Focus.
To focus, press the shutter-release
button halfway or press the AF-ON
button (the AF-assist illuminator may
light if the subject is poorly lit). If the
camera is able to focus, the focus
point will be displayed in green;
otherwise, the focus point will flash
red.
D
The AF-Assist Illuminator
Do not obstruct the AF-assist illuminator while it is lit.
Basic Photography and Playback
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