Canon EOS-1DS Mark III Instruction Manual page 83

AF: Selecting the AF Mode
_,, If focus cannot be achievea, the focus confirmation light <0> in the
we _¢finder will biink. If this occurs, a picture cannot be taken even if the
shutter button is pressed completeJy. Recompose [ne picture and try aria
focus again. Or see "When Autofocus Fails" (p.86).
_fthe [CJ: Beep] menu is set to [Off], the beeperwtJlno[ soueawhen focus is achieved.
Focus Lock
After achieving focus with One-Shot AF, you can Jock the focus on a suojecl
and recompose [ne sno[. This is called "focus lock." This is convenient when
rou want to focus a subject not covered by the Area AR
AJ Ser¢o AF for Moving Subjects
This AF mode is for moving subjects
when the focusing distance keeps
changing. While you hoJd down the
shutter button halfway, the subject
wiJJ be focused continuousJy.
® The exposure is set at the moment
the picture is taken.
® AF is also possible by pressing the
<AFoON> button.
Focus Tracking with At Servo AF
If the subject approaches or retreats from the camera at a constant rate, the
camera tracks the subiect and predicts the focusing distance immediately before
the picture is taken. This is for obtaining correct focus at the moment of exposure.
® When the AF point selection is automatic (p.84), the camera first
uses the center AF point to focus. During autofocusing, if the subject
moves away from the center AF point, focus tracking continues as
long as the subject is covered by the Area AR
® With a manually selected AF point, the selected AF point will focus
track the subject.
With AI SeEvo RE,the beeperwi!!not Soundeven when focus is ach!eved. A !sa,
the focus confirmationlight <O > inthe viewfinderwi!Jnot !ight,
83