Sony ILCE-1 a1 Help Manual page 134

If you want the face or eye detection frame to disappear within a certain period of time after the camera has focused on the face
or eye, set [AF Area Auto Clear] to [On].
Note
If the subject is moving too much, the detection frame may not be displayed correctly over their eyes.
The eye detection frame is not displayed when the Eye AF function is unavailable.
Even if [ Face/Eye Frame Disp.] is set to [Off], a green focusing frame will appear over faces or eyes that are in focus when
you press the shutter button halfway down, etc.
Related Topic
Focusing on human eyes
Face/Eye Prior. in AF (still image/movie)
Face/Eye Subject (still image/movie)
Right/Left Eye Select (still image/movie)
Face Memory
5-025-537-11(1) Copyright 2021 Sony Corporation
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