(In reply to Sebastian Luncan from comment #5)
> I've also took a picture (attached). On the left is amdgpu-dc on the right
> amdgpu, gamma 3 (xgamma -gamma 3), kernel 4.17. See the trees and the grass
> on the left. Why do they look different on the same gamma values?

Can you try if current upstream xf86-video-amdgpu Git master works better with
DC?