Because my eyes are quite sensitive, I usually use brightness level 3. In the morning, if it feels too dim, I adjust it to 4, which seems slightly brighter but still quite soft. When I switch back to 3 and then to 4 again, it appears brighter than before. I'm not sure if this is related to sleeping overnight. One day, I tried a test during the day: after closing the lid for 12 hours, I recorded a video comparison, and the brightness at level 4 appeared the same as before (with automatic brightness turned off and True Tone enabled