Nikon Df User Manual page 45

A
Detaching the Lens
Be sure the camera is off when removing or
exchanging lenses. To remove the lens, press
and hold the lens release button (q) while
turning the lens clockwise (w). After removing
the lens, replace the lens caps and camera
body cap.
A
Lens Focus Mode
If the lens is equipped with a focus mode
switch, select autofocus mode (A, M/A, or A/M).
D
CPU Lenses with Aperture Rings
In the case of CPU lenses equipped with an aperture ring (0 320), lock
aperture at the minimum setting (highest f-number).
A
Non-CPU/Non-AI Lenses
The camera can be used with non-CPU lenses and lenses not equipped
with AI mechanisms (non-AI lenses; 0 163).
A
Image Area
The DX format image area is automatically
selected when a DX lens is attached (0 51).
Image area
X
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