The Power Switch - Nikon D3000 Reference Manual

The role of the Fn (E) button can be selected using the
Buttons > /Fn button option in the setup menu
E
(0 134), allowing the following settings to be
adjusted by pressing the Fn (E) button and rotating
the command dial:
Release mode (0 53)
X
Image quality and size (0 50)
ISO sensitivity (0 62)

The Power Switch

Rotate the power switch as shown to turn the camera
on.
Rotate the power switch as shown to turn the camera
off.
10
Fn (E) button
White balance (0 80)
Active D-Lighting (0 64)
Set framing grid (0 132)
+
Command dial
Viewfinder