Graphical brightness problem.

I wonder if it is a matter on PC or not. I have four different PC, with Nvidia or AMD graphical card. All are pretty solid and halo wars 2 runs at 19201080 or 25601440 really fast.
When you are in game, i see the brightness corrects it self automatically. When you go on a high light part of a map, screen turns slowly but clearly in low brightness. As soon, as you go on a more darker part, brightness comes higher.
It seems to be the same as for the newest TV screens, where they adapt in fonction of the brightness of the movie.
Fact is on HW2, on some sands map, units nearly turns in real “dark” units, (blue or red turns in something really unshiny) you just want to light up your screen. So i have to click out side the map (the fogged one) to come back on my units and see them shiny again for some seconds.

I don’t find any option to avoid this automatic adjustment. I don’t know if it is the same on Xbox, but it is harder to know if it comes from the tv screens software or the game.
On PC screen, it is the first time, i notice that on a game.
Today, i nearly stop playing HW2 cause of this annoying matter (for me), and wonder if i ll buy HW2 on Xbox one to enjoy it. (in fact buy a xbox one, to play this game)

If someone can help me, or if it is a known bug, just say it please.

I think this is the HDR, but i see no option to disable it (and i remember a patch allowing that on xbox one cause it wasn’t available for this plateforme, perhaps you can disable it)

Best regards!