Thank you all. I have been comparing photos from when I had the D3s that I shot at 12,800 to ones from the D4 the D4's are much cleaner - however in all fairness the D3s was 12 MPs as the D4 has 17.2 so that's were the difference is just that little bit of resolution. However there are more apparent differences between the 2 such as DR, focus speed, video,etc.