Nikon D300 User Manual page 261

AF point among the 51 points in the
Multi Selector.
Once good focus has been achieved with your selected AF
point, the camera can track the subject, even if your selected
AF point loses focus on the subject. It does this by allowing
you to select patterns of extra AF points surrounding your
single selected AF point. The patterns are
and 51 points. There's even a
available, which works great for subjects moving erratically,
including toward or away from you.
patterns, in red, that would be active if you were using the
center AF point in the Viewfinder.
Of course, if you select
If you select 9 points
smaller pattern around the
Selector. Unfortunately, you can only see the primary selected
AF point moving in the Viewfinder, not the pattern. You'll
have to imagine one of the red patterns moving with your
selected AF point, which will be in the center of the pattern.
Figure 4-7. Viewfinder with AF point comparison
We'll discuss this even more deeply in the chapter titled
Chapter 11. This chapter only addresses how to configure the
setting.
51 points (3D tracking)
51 points, all the AF points are active.
or 21 points, you can move the entire
Viewfinder
261
Viewfinder by using the
9 points,
Figure 4-7 shows the
using the
21 points,
mode
Multi