The Canon 1D X is the most expensive among the mainstream, full frame, professional DSLRs out there, and its scores on DxOMark aren't going to help the camera sell...
DxOMark's tests involve many aspects of the camera and weigh these aspects differently. So in quite a few circumstances, the certainly has an edge. But when talking about pure image quality issues -- like ISO, dynamic range, and color depth -- the 1D X falls short, almost tying Nikon's three-year-old flagship while the D4 really jumps ahead in ratings.
DxOMar's ratings are generally controversial for their 'overall' scoring. But what do you guys think? Should Canon have stepped it up for such an expensive camera?