Use the Quick shot feature to take photos immediately even without screen unlock.
Press the volume down button twice when the screen is off or locked.
This will launch the Camera app, and a single photo will be taken.
• The Camera app will remain open after taking a Quick shot; you can continue to take photos.
• Press the volume down key twice with the Quick Cover closed. The Camera app will run as it normally does, even when the quick cover is closed.
• The Quick shot feature always runs the camera in general mode. After taking a photo using the Quick shot feature, the camera can be used in a different mode.
• The Quick shot feature can be turned on or off in 'Settings> Shortcut key.'