Sony Cyber-shot DSC-RX100M3 Instruction Manual page 118

The product continues to focus while the shutter button is pressed and held halfway down. Use this
when the subject is in motion.
(DMF):
Allows you to use manual focus and auto focus in combination.
(Manual Focus):
Adjusts the focus manually.
Note
If the subject is too close, the image may show any dust or fingerprints on the lens. Wipe the lens
with a soft cloth, etc.
When [Focus Mode] is set to [Continuous AF], the beep does not sound when focus is achieved.
[56] How to Use
Focus Area
Selects the focusing area. Use this function when it is difficult to get the proper focus in auto focus
mode.
1. MENU → (Camera Settings) → [Focus Area] → desired setting.
Menu item details
Wide:
Focuses automatically on a subject in all ranges of the image.
When you press the shutter button halfway down in still image shooting mode, a green frame is
displayed around the area that is in focus.
Center:
Focuses automatically on a subject in the center of the image. When used together with the AF lock
function, you can compose the image you want.
Flexible Spot:
Allows you to move the AF range frame to the desired point on the screen and focus on an extremely
small subject in a narrow area.
On the Flexible Spot shooting screen, you can change the size of the AF range finder frame by rotating
the control wheel.
Lock-on AF:
When the shutter button is pressed and held halfway down, the product tracks the subject within the
selected autofocus area. Point the cursor to [Lock-on AF] on the [Focus Area] setting screen, then select
the desired tracking start area using the left/right sides of the control wheel. You can move the tracking
start area to the desired point by designating the area to be the flexible spot.
On the Flexible Spot shooting screen, you can change the size of the AF range finder frame by rotating
the control wheel.
Using shooting functions Adjusting the focus