Nikon D500 User Manual page 138

AF-S focus mode: Focus locks automatically when the in-focus
indicator (I) appears, and remains locked until you remove
your finger from the shutter-release button. Focus can also
be locked by pressing the center of the sub-selector as
described on the previous page.
3
Recompose the
photograph and shoot.
Focus will remain locked
between shots if you keep
the shutter-release button
pressed halfway (AF-S) or
keep the center of the sub-
selector pressed, allowing several photographs in succession
to be taken at the same focus setting.
Do not change the distance between the camera and the
subject while focus lock is in effect. If the subject moves, focus
again at the new distance.
A
Locking Focus with the AF-ON Button
During viewfinder photography, focus can be locked using the AF-ON
button in place of the shutter-release button (0 102). If AF-ON only is
selected for Custom Setting a8 (AF activation, 0 293), the camera will
not focus when the shutter-release button is pressed halfway; instead,
the camera will focus when the AF-ON button is pressed, at which point
focus will lock and remain locked until the AF-ON button is pressed
again.
A
See Also
See Custom setting c1 (Shutter-release button AE-L, 0 296) for
information on using the shutter-release button to lock exposure.
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