HID lights are bright.  Really bright.  Sometimes a little too bright.  Have you ever been driving at night and have some one's headlights blindingly blast into your car.
   That’s why many auto manufacturers like BMW have auto leveling xenon headlights. The newest cars have multiple features in the auto leveling system, with the most basic being the brights to no brights adjustment. You can’t see and it can be a little dangerous sometimes. They have a few different features depending on the year of the car as features keep getting added.    When you brights are on theheadlight actually rotates up to project in a straight path and light up everything in front of it.  When the brights are off they drop back down and project towards the ground more, controlling the spray of light.
   HID auto leveling systems can be installed in vehicles that do not have them, however it can be expensive.  If you don’t want to spend the money for auto leveling regular fixed xenon lights will be bright enough where you   won’t even notice the subtle changes because just about everything is lit up by the xenon light.

   Another feature that is a bit more advanced is real time auto leveling.  As you drive down the road you hit little bumps and terrain changes like small hills and big curves.  As your vehicle moves over a bump for instance, the lights go up a little with the car and then back down when the headlights are fixed in position to the vehicle.