Samsung SM-G930F - Manual (Page 89)

Applications
89
Separating the focus area and the exposure area
You can lock the focus and the exposure on a selected area to prevent the camera from
automatically based on changes to the subjects or light sources. In pro mode, you can
separate the exposure and focus and set them to different points.
This feature is only available when you set the shutter speed and the focus to Auto in
pro mode.
1
On the preview screen, tap and hold the area to focus.
The AF/AE frame will appear on the focus area.
2
Drag the AF/AE frame to the exposure area.
The exposure area will be separated from the focus area.