Ai Servo Af For Moving Subjects; Ai Focus Af For Automatic Switching Of Af Mode - Canon EOS 550D Instruction Manual

AF: Changing the AF Mode*
viewfinder will blink, !f this occurs, a picture cannot be taken even if the
shutter button is pressed completely, Recompose th e p!cture and try to
focus again, Or see !!When Autofocus Fails" (p_202),
® If the [1_ Beep] menu is set to [Disabme], the beeper wiJ! not sound when
focus is achieved
AJ Servo AFfor 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 wHJ be focused continuousJyo
® The exposure is set at the moment the picture is taken.
® When the AF point selection (p.68) is automatic, 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 another AF point.
With AI SeEvo AF, the beepe[ _ill not Soundeven when focus is achieved.
Also, the focus confirmation _ight<@> in the viewfinderwill not light.
AJ Focus AF for Automatic Switching of AF Mode
AI Focus AF switches the AF mode from One-Shot AF to AI Servo
AF automatically if the still subject starts moving.
® After the subject is focused in the One-Shot AF mode, if the subject
starts moving, the camera will detect the movement and change the
AF mode automatically to AI Servo AF.
When focus is achieved in the AI Focus AF mode With the Servo mode
active, the beeper wi!l sound softiy However,the focus confirmation light
<0> in the viewfinder will not light.
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