Sony DSC-RX100M3 - Manual (Page 108)

[103] How to Use Using shooting functions Recording movies
Auto Slow Shut. (movie)
Sets whether or not to adjust the shutter speed automatically when recording movies if the
subject is dark.
1. MENU
→ (Camera Settings) → [
Auto Slow Shut.]
→ desired setting.
Menu item details
On (default setting):
Uses [ Auto Slow Shut.]. The shutter speed automatically slows when recording in dark
locations. You can reduce noise in the movie by using a slow shutter speed when recording
in dark locations.
Off:
Does not use [ Auto Slow Shut.]. The recorded movie will be darker than when [On] is
selected, but you can record movies with smoother motion and less object blur.
Note
[ Auto Slow Shut.] does not function in the following situations:
When [Movie] in shooting mode is set to [Shutter Priority] or [Manual Exposure].
When [ISO] is set to other than [ISO AUTO] .
[104] How to Use Using shooting functions Recording movies
MOVIE Button
Sets whether or not to activate the MOVIE button.
1. MENU
→ (Custom Settings) → [MOVIE Button] → desired setting.
Menu item details
Always (default setting):
Starts movie recording when you press the MOVIE button in any mode.
Movie Mode Only:
Starts movie recording when you press the MOVIE button only if the shooting mode is set to
[Movie] mode.