when importing .mov the footage gets darker.

So I built a new computer and installed after effects CS5 and when I import footage from my 5d mark ii camera. The footage gets darker and when I render the same footage with out any effects, it comes out as the original. So after effects is viewing the footage darker, but not acctually changing it.

I'm runing windows 7 64-bit, AE CS5

32gb ram

2x Nvidia GTX 770

I just built it and maybe I didn't install somthing to make it work correctly. But all hardware works.