u/planerbeat

On my Samsung S90D QD-OLED, Movie and Filmmaker modes are completely broken for HDR and HDR10+ content. In dark scenes, shadows turn into a blocky, solid gray mess that looks like severe posterisation. Interestingly, every other picture mode handles these same scenes perfectly. After some troubleshooting, I narrowed it down to the ambient light sensor. Even though I have all energy-saving settings turned off, the sensor still seems to be active in these specific modes. If the room is pitch black, the shadows look fine. But as soon as I shine a flashlight at the sensor, the blacks immediately wash out into gray. I just updated to firmware 2123, but the bug is still there.