Canon EOS REBEL T5 Instruction Manual page 155

Cautions for movie shooting are on pages 177 and 178.
If necessary, also read the Live View shooting cautions on pages
151 and 152.
The ISO speed (ISO 100 - ISO 6400), shutter speed, and aperture are
set automatically.
You can press the <A> button (p.116) to lock the exposure (AE lock).
The exposure setting will be displayed for the number of seconds set
with [Z2: 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.
Pressing the shutter button halfway displays the shutter speed and ISO
speed on the screen's bottom. This is the exposure setting for still photo
shooting (p.158). 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
With autoexposure movie shooting, the camera will automatically turn
on the Speedlite's LED light under low-light conditions. For details,
refer to the EX Speedlite's instruction manual.
k Shooting Movies
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