Canon Rebel T3 Series Cameras: Quick Mode Autofocusing in Live View
As its name implies, Quick mode offers the fastest autofocusing during Live View or movie shooting with a Canon Rebel T3 or T3i digital SLR. It also is the most similar to the autofocusing system used for regular viewfinder photography, based on the same nine-point focusing grid.
Set the lens switch to the AF position.
Engage the Live View or Movie display.
For Live View: Press the Live View button.
For Movie recording: Turn the Mode dial to the little movie-camera icon, and the live preview appears without further ado.
Press the Quick Control button, highlight the Autofocus mode icon, and rotate the Main dial to set the mode to Quick.
Rectangles representing the nine autofocus points appear in the center of the screen.
If you're using Movie, P, Tv, Av, M, or A-DEP, set the AF Point Selection mode.
This option tells the camera which of the autofocus points you want it to consider when it sets focus. You have two choices:
Automatic: All nine autofocus points are active, and the camera decides which one to use when setting the focus distance — again, usually selecting the closest object as the focus target.
Manual: You select which of the nine focusing points you want the camera to use.
Press the up cross key to highlight the autofocus points. (If the camera shifts out of Quick Control mode before you get to this point, just press the Quick Control button, highlight the AF mode icon again, and then press up or down.) When all nine points are highlighted, automatic focus-point selection is in force. The label at the bottom of the screen reminds you of that fact. Rotate the Main dial to shift to manual point selection; continue rotating the dial until the point you want to use is highlighted.
Press the shutter button halfway and release it to exit the Quick Control display.
Frame your shot so that your subject falls under the selected autofocus point(s).
Press and hold the shutter button halfway down to focus.
As soon as you press the button, the monitor turns black and the autofocusing mechanism kicks into gear. Keep pressing the button until the camera beeps and the Live View display reappears. The beep signals you that focus is set; one or more of the focus points appears green to tell you which areas of the frame are in focus. If the camera can’t find a focusing target, the focus point turns orange and blinks. Try using manual focusing instead.
After focus is established, press the shutter button all the way to take your picture. Or to start recording a movie, release the shutter button and then press the Live View button. (Focus will remain set at the point you just established.) Press the Live View button again to end the recording.