Nikon D300 User Manual page 651

Before you turned the
happily controlling both shutter speed and aperture for you.
When you turned the dial, the camera immediately switched
to Flexible program
Control panel, and let you have control of the aperture while
it controlled only the shutter speed. In effect, the D300(S)
allowed you to exercise your knowledge of photography very
quickly and only assisted you from that point.
When you enter
the aperture, and the D300(S) controls the shutter speed. If
you turn the Main command dial
smaller. Turn it to the right and the aperture gets larger.
Nothing happens if you turn the
only gave you control of the aperture in
mode. Can you see why I say that
like A – Aperture priority auto
Counting Clicks in P Mode
If your D300(S) is in P mode and you turn the Main
command dial to the right, the camera goes into P* mode
and starts counting clicks to the right. In order to get back
into normal P mode, you have to turn the Main command
dial back to the left that same number of clicks (up to 15
clicks). The reason I know that the D300(S) is actually
counting clicks is that I decided to count along one day.
Here's what I did: I set my camera to P mode and got into
a darker area where the lens was at maximum aperture. I
then started cranking the Main command dial to the right,
which should increase the aperture. Since I was already at
maximum aperture, the camera could not increase the
aperture size, so it just sat there counting clicks instead. In
Main command
mode, put an asterisk after the
P* – Flexible program
651
dial, the camera was
mode you control only
to the left, the aperture gets
Sub-command
Flexible program
Flexible program
mode?
P on the
dial. Nikon
mode acts