Sony Cyber-shot DSC-RX100 IV - Manual (Page 76)

The image is displayed on the screen only regardless of the [FINDER/MONITOR] setting.
When you look into the viewfinder
The image is displayed in the viewfinder only regardless of the [FINDER/MONITOR] setting.
When you are not looking into the viewfinder or when shooting
a self-portrait
If [FINDER/MONITOR] is set to [Auto], the image is displayed only on the screen.