Canon EOS 750D Instruction Manual page 223

General Movie Shooting Cautions are on pages 253-254.
If necessary, also read the General Live View Shooting Cautions on
pages 218-219.
In Basic Zone modes, the shooting result will be the same as with <A>.
Also, the scene icon for the scene detected by the camera is displayed
on the upper left (p.224).
In the <f> and <s> shooting modes, movies will be taken with the
same settings as in the <d> mode.
Settable menu functions differ between Basic Zone modes and Creative
Zone modes (p.358).
Shutter speed and aperture are set automatically.
In Creative Zone modes, you can press the <A> button (p.162) to lock
the exposure (AE lock). The exposure setting will be displayed for the
number of seconds set with [Z1: 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.)
In Creative Zone modes, you can hold down the <g> button and turn
the <6> dial to 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 taking a
still photo (p.227). 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).
ISO Speed in Basic Zone Modes
The ISO speed will be set automatically within ISO 100 - ISO 6400.
ISO Speed in <d>, <s>, and <f> Modes
The ISO speed will be set automatically within ISO 100 - ISO 6400.
Under [54: Custom Functions (C.Fn)], if [2: ISO expansion] is set
to [1: On], the maximum speed will be expanded to H (equivalent to
ISO 12800).
Under [54: Custom Functions (C.Fn)], if [3: Highlight tone priority]
is set to [1: Enable], the ISO speed will be ISO 200 - ISO 6400.
k Shooting Movies
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