I just tested my NX1 using GammaDR, and sharpening at -5. I shot in UHD, downscaled in Premiere Pro to 1080, and rendered out to a DVD. The sharpening looks horrible, and very “video”-ish. The in-camera sharpening is using a contrast-type of sharpening that produces artifacts in a radius around high-contrast objects. You can confirm this increased contrast on a lumetri-scope. On the other hand, setting sharpening at -10 produces beautiful results (without any post-sharpening), and none of the artifacts.