Canon EOS REBEL T6 (W) Basic Instruction Manual page 87

General Movie Shooting Cautions are on pages 91-92.

If necessary, also read General Live View Shooting Cautions on

pages 81-82.
The ISO speed (ISO 100 - ISO 6400), shutter speed, and aperture are

set automatically.
You can press the <A> button to lock the exposure (AE lock). The

exposure setting will be displayed for the number of seconds set with
[k2: Metering timer]. After applying AE lock during movie shooting,
you can cancel it by pressing the <S> button. (AE lock setting is
retained until you press the <S> button.)
By holding down the <O> button and turning the <6> dial, you can

set the exposure compensation.
If you shoot a movie with autoexposure, the ISO speed, shutter speed,

and aperture will not be recorded in the movie's Exif information.
With autoexposure movie shooting, the camera will automatically turn on

the Speedlite's LED light under low-light conditions. For details, refer to
the Speedlite's instruction manual.
k Shooting Movies
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