For subject-tracking AF, we recommend that you set focus and AF-area mode respectively to AF-C and Autoarea AF. Once tracking starts, focus will follow the subject through the frame while the AF-ON button is pressed or the shutter-release button is pressed halfway (note that the discussion in this section applies only from camera "C" firmware version 3.00).
Before proceeding, position the focus point as desired.
To start subject tracking, wait until the chosen focus point is over your subject and then either press the shutter-release button halfway or press the AF-ON button: the focus point will turn amber and the camera will track the subject until the chosen button is released. Subject tracking can also be started by pressing or tapping your subject in the display.
To suspend subject tracking and restore the focus point selected before tracking started, lift your finger from the shutter-release or AF-ON button. If you started subject tracking by pressing or by tapping your subject in the display, you can press to suspend tracking and select the center focus point.