The CX has good SDR peak brightness, enough to combat glare in most rooms. It has an Automatic Brightness Limiter (ABL) that significantly dims the screen when large areas get bright, so that’s why the ‘Peak 100% Window’ and ‘Sustained 100% Window’ tests result in significantly less brightness.
Like the LG C9 OLED, the CX has a Peak Brightness setting, which changes the way the ABL performs. With this setting turned ‘Off’, most scenes are between 294 to 308 cd/m², and if the entire screen is bright, the brightness is 166 cd/m². Turning this setting to ‘High’, which is what we tested with, makes most scenes brighter, but large areas are less bright.
The measurements were taken post-calibration in the ‘Expert (Dark Room)’ Picture Mode, with OLED Light to ‘100’ and Peak Brightness to ‘High.’ Before calibration, the TV was slightly less bright.