Nikon Coolpix B500 Reference Manual page 71

Using the Snap-back Zoom
If you lose sight of the subject while shooting with the lens in telephoto position,
press the q (snap-back zoom) button to temporarily widen the visible area so that
you can frame the subject more easily.
q button
While pressing the q button, frame the subject inside the framing border of the
shooting screen. To widen the visible area further, move the zoom control toward
f while pressing the q button.
Release the q button to return to the original zoom position.
Snap-back zoom is not available during movie recording.
Shooting Features
Using the Zoom
Framing border
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2 5 m 0 s 2 5 m 0 s
3 2 0 0 3 2 0 0