Sony ILCA-99M2 Manual page 270

During continuous shooting, the product automatically shoots with Continuous AF from the
second shot.
(Continuous AF):
The product continues to focus while the shutter button is pressed and held halfway down. Use
this when the subject is in motion. In [Continuous AF] mode, there is no beep when the camera
focuses.
(DMF):
You can make fine adjustments manually after the focus is locked, letting you focus on a subject
more quickly than when using the manual focus from the beginning. This is convenient in
situations such as macro shooting.
(Manual Focus):
Adjusts the focus manually. If you cannot focus on the intended subject using auto focus, use
manual focus.
Focus indicator
(lit):
The subject is in focus and the focus is locked.
(flashing):
The subject is not in focus.
(lit):
The subject is in focus. The focus will be adjusted continuously according to the movements of
the subject.
(lit):
Focusing is in progress.
Subjects on which it is difficult to focus using auto focus
Dark and distant subjects
Subjects with poor contrast
Subjects seen through glass
Fast-moving subjects
Reflective light or shiny surfaces
Flashing light
Back-lit subjects
Continuously repetitive patterns, such as the facades of buildings
Subjects in the focusing area with different focal distances
Note
Only [Continuous AF] and [Manual Focus] are available in the movie shooting mode.
Hint
In [Continuous AF] mode, you can lock the focus by pressing and holding the button that has been
assigned the [Focus Hold] function.