P (Programmed Auto); S (Shutter-Priority Auto) - Nikon Z fc N2016 Reference Manual

Mode
M Manual

P (programmed auto)

･ In this mode, the camera automatically adjusts shutter speed and
aperture according to a built-in program to ensure optimal exposure
in most situations.
･ Different combinations of shutter speed and aperture that produce
the same exposure can be selected by rotating the main command
dial ("flexible program").
- While flexible program is in effect, a flexible program indicator ( U ) is
displayed.
- To restore default shutter speed and aperture settings, rotate the
main command dial until the indicator is no longer displayed.
Flexible program also ends when the mode dial is rotated to
another setting or the camera is turned off.

S (shutter-priority auto)

･ In shutter-priority auto, you choose the shutter speed while the
camera automatically adjusts aperture for optimal exposure. Choose
The mode selector
Description
You control both shutter speed and aperture.
Set shutter speed to "bulb" or "time" for long
time-exposures.
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