Sony alpha ILCE-5100 Help Manual page 187

Help Guide
How to Use
Interchangeable Lens Digital Camera
ILCE-5100
Center Lock-on AF
When you press the center button, the camera detects the subject positioned in the center of the screen and continues
to track the subject.
1. MENU → (Camera Settings) → [Center Lock-on AF] → [On]
2. Align the target frame (A) over the subject and press
MENU → (Camera Settings) → [Center Lock-on AF] → [Off].
3. Press the shutter button fully down to shoot the image.
Note
[Center Lock-on AF] may not function very 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.
Lock-on AF does not work in the following situations:
In [Sweep Panorama] mode
When [Scene Selection] is set to [Hand-held Twilight] or [Anti Motion Blur]
When shooting in Manual Focus mode
When using the digital zoom
When the subject to be tracked disappears from the screen, Lock-on AF is released.
When [Center Lock-on AF] is set to [On], the camera may not be able to resume tracking for a while after it loses the
track of the subject.
in the center of the control wheel. To stop tracking, select
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