Canon EOS REBEL T6 (W) Basic Instruction Manual page 80

Using AF to Focus (AF Method)
If focus is not achieved with the shooting conditions on the preceding

page, set the lens's focus mode switch to <MF> and focus manually.
If you use AF with any of the following lenses, using [Quick mode] is

recommended. Autofocusing with [FlexiZone - Single] or [u Live
mode] may take longer or correct focus may not be achieved.
EF50mm f/1.4 USM, EF50mm f/1.8 II, EF50mm f/2.5 Compact Macro,
EF100mm f/2.8 Macro USM, EF75-300mm f/4-5.6 III,
EF75-300mm f/4-5.6 III USM
For information on other lenses, refer to the Canon Web site.
If you shoot a peripheral subject and it is slightly out of focus, aim the

center AF point over the subject to focus, focus again and then take the
picture.
The AF-assist beam will not be emitted. However, if an EX-series

Speedlite (sold separately) equipped with an LED light is used, the LED
light will turn on for AF-assist when necessary.
In magnified view, focusing may be difficult due to camera shake. Using

a tripod is recommended.
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