Sony alpha 7R IV Instruction Manual page 48

Shooting movies
Changing settings for movie recording
File Format
Selects the movie file format.
MENU 
setting.
File Format
XAVC S 4K
XAVC S HD
AVCHD
For details on memory cards that can be used for these formats, refer to
page 83.
GB
48
(Camera Settings 2)  [ File Format]  desired
Characteristics
Records movies in 4K resolution
(3840×2160).
Records movies in crisper quality
than AVCHD with larger amounts
of data.
The AVCHD format has a high
degree of compatibility with
storage devices other than
computers.
You can save movies on
a computer using the
PlayMemories Home
software.
You can save movies on
a computer or create
a disc that supports
this format using the
PlayMemories Home
software.