Canon EOS Rebel T6 Instruction Manual page 100

S Selecting the AF PointN
Shooting Tips
When shooting a portrait up close, use One-Shot AF and focus

on the eyes.
If you focus on the eyes first, you can then recompose and the face
will remain sharp.
If it is difficult to focus, select and use the center AF point.

The center AF point is the most sensitive among the nine AF points.
To make it easier to focus on a moving subject, set the camera

to automatic AF point selection and AI Servo AF (p.98).
The center AF point will first be used to focus on the subject. 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.
AF-Assist Beam with the Built-in Flash
Under low-light conditions, when you press the shutter button halfway,
the built-in flash may fire a brief burst of flashes. This illuminates the
subject to help autofocusing.
AF-assist beam will not be emitted from the built-in flash in <7>, <3>,

or <5> mode, or when [Built-in flash firing] is set to <b> in <C> or
<P> mode.
The AF-assist beam will not be emitted with AI Servo AF operation.

The effective range of the AF-assist beam emitted by the built-in flash is

approx. 4 meters / 13.1 feet.
In Creative Zone modes, when you raise the built-in flash with the <I>

button (p.104), the AF-assist beam will be emitted when necessary. Note
that depending on the setting for [7: AF-assist beam firing] under [53:
Custom Functions (C.Fn)], AF-assist beam will not be emitted (p.264).
If you use an Extender (sold separately) and the maximum aperture
becomes higher than f/5.6, AF shooting will not be possible (except in
[FlexiZone - Single] and [u Live mode] during Live View shooting). For
details, refer to the Extender's instruction manual.
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