Canon EOS 550D Instruction Manual page 30

Using AF to Focus
,3
Focus the subject.
_ Aim the AF point over the subject and
press the shutter button halfway.
_y,, T he Live View image will turn off, the
reflex mirror will go back down, and
AF will be executed.
_y,, W hen focus is achieved, the beeper
will sound and the Mve View image
will reappear.
_y,, T he AF point used to focus will light in
red.
Take the picture.
_ Check the focus and exposure, then
press the shutter button completely to
take the picture (p.108).
You Cannot take a pictu[e during autofocusing. Take the picture 0nly While
the Live View image is displayed,
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