Canon EOS REBEL T2I Instruction Manual page 59

Shooting Function Settings
[',_,_] Menu
® Movie exposure
Normally, set this option to [Auto].
Setting [Movie exposure] to [Manual] enables you to manually set
the ISO speed, shutter speed, and aperture for movie shooting
(p.127).
® Grid display
With [Grid 1 :_] or [Grid 2_], you can display grid lines.
® Metering timer
You can change how long the exposure setting is displayed (AE lock
time).
® Sound recording
When the sound recording is set to [On], monaural sound will be
recorded with the built-in microphone. Stereo sound recording is
possible by connecting an external microphone (commercially
available) equipped with a stereo mini plug (3.5mm dia.) to the
camera's external microphone iN terminal (p.16). The sound
recording level will be adjusted automatically.
® _Nighiight tone priority
This can be set only when [Movie exposure] is set to [Manual].
if [Enable] is set, highlight detail will be improved. The dynamic
range is expanded from the standard 18% gray to bright highlights.
The gradation between the grays and highlights becomes smoother.
The iSO speed range will be ISO 200 ° 6400. The Auto Lighting
Optimizer will also be set automatically to [Disable] and cannot be
changed.
_The Grid display and Metering timer Settingswill also be reflected in Liye
View shooting.
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