The S ( Q ) Button; Adjusting Iso Sensitivity - Nikon D780 Reference Manual

The S ( Q ) Button

Use the S ( Q ) button to adjust the camera's sensitivity to
light (ISO sensitivity). The higher the ISO sensitivity, the less light
needed to make an exposure, allowing faster shutter speeds or
smaller apertures. You also have the option of enabling auto ISO
sensitivity control, which automatically adjusts sensitivity if
optimal exposure cannot be achieved at the setting selected by
the user.

Adjusting ISO Sensitivity

Hold the S ( Q ) button and rotate the main command dial.
•
Choose from values of from ISO 100 to 51200. Settings of from
about 0.3 to 1 EV below ISO 100 and 0.3 to 2 EV above ISO
51200 are also available.
•
In addition to settings of from ISO 100
to 51200, b and all EFCT modes other
than j also offer an X ([Auto])
option. When X is selected, the
camera adjusts ISO sensitivity automatically.
Camera Controls
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