Sorry, I meant to say brightness contrast: high-end dynamic displays will turn off backlighting in black areas, and turn them all the way up in white areas.

Let's say your movie shows a full moon in the night. Looking at that moon on the screen is now like looking at a torchlight in the night in real life. The moon section of the screen is blasting high brightness right at your eyes.

This is what I meant. I tried doing office work on such a monitor, and quickly realize it's good for immersion, but terrible for office work, for which you want stable brightness.