Sony ILCE-7 How To Use Manual page 68

[56] Using shooting functions > Adjusting the focus
Lock-on AF (On)
Maintains the focus on a moving subject automatically.
1. MENU →
2. Align the target frame and the subject to be tracked, and press
Note
The [Lock-on AF] function may not operate well in the following situations:
The subject is moving too quickly.
The subject is too small, or too large.
The contrast between the subject and the background is poor.
It is dark.
The ambient light changes.
Hint
If you lose track of the subject, this product can detect the subject and resume the Lock-on
AF function when the subject reappears on the screen.
[57] Using shooting functions > Adjusting the focus
Pre-AF (still image)
The product automatically adjusts focus before you press the shutter button halfway down.
1. MENU →
Menu item details
(Camera Settings) → [Lock-on AF] → [On].
(Custom Settings) → [ Pre-AF] → desired setting.
in the center.