This is how you enable HDR (High Dynamic Range) for The Division 2 :
1. If you are on console, make sure to enable HDR in your console's settings (Playstation 4, Xbox One). Please be aware that you need a screen that supports HDR technology as well - you'll be able to find out in your monitor's or TV's manual.
2. Launch The Division 2.
3. From the main menu, navigate to Settings > Graphics
4. There, you'll be able to adjust two parameters to optimise the effects of HDR to your liking.
You'll be able to go back and change the settings at any time.