C.fn Iii: Autofocus/Drive; Highlight Tone Priority  - Canon EOS 7D Instruction Manual

C.Fn II -3
0: Disable
1: Enable
Improves the highlight detail. The dynamic range is expanded between
the standard 18% gray and bright highlights. The gradation between the
grays and highlights becomes smoother.
With setting 1, the [Disable] setting automatically takes effect for the

Auto Lighting Optimizer (p.77) and it cannot be changed.
With setting 1, noise in the shadow areas may be slightly more than

usual.
With setting 1, the settable ISO speed range will be 200 - 6400.
Also, <A> will be displayed on the LCD panel and in the viewfinder.

C.Fn III: Autofocus/Drive

C.Fn III -1
During focusing in AI Servo AF mode, the AF sensitivity for tracking
subjects (or obstacles) moving into AF points can be set to one of five
levels.
If it is set toward [Slow], interruptions by any obstacles will be less
disruptive. It makes it easier to keep tracking the target subject.
If it is set toward [Fast], it will be easier to focus any subjects which
suddenly enter the picture from the side. Convenient when you want to
successively photograph multiple subjects located at random distances.
Highlight tone priority
AI Servo tracking sensitivity
3 Custom Function SettingsN
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