Panasonic Lumix S1R Operating Instructions Manual page 530

Firmware Ver. 1.3
Dividing Files When Recording Videos (CFexpress Cards)
[Rec. File Format]
[MP4]
F-10
[Rec Quality]
FHD
4K
Size interval for dividing files
A new file will be created to continue
recording if the continuous recording
time exceeds 30 minutes or the file size
exceeds 4 GB.
When using a CFexpress card of
32 GB or less:
A new file will be created to continue
recording if the file size exceeds 4 GB.
When using a CFexpress card over
32 GB:
Files are not divided for recording.