Custom Setting #A9 Autofocus Assist Illumination - Nikon D300 Complete Manual

11 points
Recommendation:
1. Use 11 points for one reason only: speed. This function
allows you to select an autofocus sensor from one side to
another faster (takes less presses on the Direction pad).
Note the word "initial" in my description above. Setting
the lower value doesn't take the 51 sensors out of use
when you're in Dynamic Area autofocus! You're only
restricted to selecting the initial focus area from 11.
Indeed, many sports or action shooters are going to want
to explore this option, as it gets them to an initial focus
point faster, but doesn't compromise the final focusing.
51 point

Custom Setting #A9 Autofocus Assist Illumination

(Built-in AF-assist illumination)
The D300's Autofocus Assist lamp is controlled by this
function:
On
Thom Hogan's Complete Guide to the Nikon D300
The camera uses only 11 sensors for initial
sensor selection
11 point
In poor lighting, the Autofocus Assist light on
the camera illuminates [default]
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