http://www.prepar3d.com/news/2013/10/4507/

 

What do I gain for selecting HDR in my graphics settings? Any link to screenshots with HDR and without HDR keeping everything else in context?  I don't have access to my P3D machine for me to try this out.

High Dynamic Range - Gives the sim a more realistic setting for color and lighting representation. Keep in mind that it will take a toll on FPS. 

 

It also kind of does what bloom did in FSX at night in relation to runway lights, etc.