Samsung RL19PSUSQ - Manual (Page 60)

Menu Description
OSD Lock & Unlock
After push the "MENU" button more than 5 seconds, OSD function is
locked (unlocked).
MagicBright™
Menu Description
MagicBright™
Then push the MagicBright button again to circle through available
preconfigured modes.
- Six different modes (Custom/Text/Internet/Game/Sport/Movie)
Brightness