Canon EOS Rebel T1i Instruction Manual page 233

A Live View ShootingN
To change the Live View settings, use the [6 Live View
function settings] menu.
Battery Life with Live View Shooting
Temperature
At 23°C / 73°F
Press the <A> button to display
the Live View image.
Press the <w> button to focus.
Press the shutter button to take
the picture.
No Flash
Approx. 190 shots
50% Flash Use
Approx. 170 shots
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