Canon EOS Rebel T4i 18-135mm IS STM Lens Kit Instruction Manual page 152

A Menu Function Settings
Metering timerN
You can change how long the exposure setting is displayed (AE lock
time). In Basic Zone modes, metering timer is fixed at 16 sec.
The Live View shooting will stop with any of the following operations. To
resume Live View shooting, press the <A> button again.
• When selecting [z3: Dust Delete Data], [53: Sensor cleaning],
[54: Clear settings], or [54: z firmware ver.]
• When changing the shooting modes (Basic Zone modes ↔ Creative
Zone modes, setting to <F> or <G> mode)
Even if a low ISO speed is set, noise may be noticeable in the displayed
Live View image under low light. However, when you shoot, the image
recorded will have minimal noise. (The image quality of the Live View
image is different from that of the recorded image.)
152