Canon EOS Rebel T4i 18-135mm IS STM Lens Kit Instruction Manual page 171

Cautions for movie shooting are on pages 195 and 196.
If necessary, also read the Live View shooting cautions on pages
165 and 166.
In Basic Zone modes, the shooting result will be the same as in the
<A> mode. Also, the scene icon for the scene detected by the camera
is displayed on the upper left (p.172).
Settable menu functions will differ between Basic Zone modes and
Creative Zone modes (p.318).
In the <f> and <s> shooting modes, the settings will be the same
as in the <d> mode.
The ISO speed (100-6400), shutter speed, and aperture are set
automatically.
In Creative Zone modes, you can press the <A> button to lock the
exposure (AE lock, p.121). 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.)
In Creative Zone modes, you can hold down the <O> button and turn
the <6> dial to set the exposure compensation.
Pressing the shutter button halfway displays the shutter speed, aperture,
and ISO speed on the screen's bottom. This is the exposure setting for
taking a still photo (p.175). The exposure setting for movie shooting is
not displayed. Note that the exposure setting for movie shooting may
differ from that for still photo shooting.
If you shoot a movie with autoexposure, the shutter speed and aperture
will not be recorded in the image information (Exif).
Using an EX-series Speedlite (Sold Separately) Equipped with an LED Light
This camera is compatible with the function turning on the LED light
automatically in low-light conditions during autoexposure shooting. For
details, refer to the Speedlite's instruction manual.
k Shooting Movies
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