Dylan777 said:
Thank you all for your feedbacks.
f8 AF seems to be the key for many to upgrade. I'm more like a fast primes(85f1.2 135f2 200f2) type of guy, f8 AF and video are not my top priority.
Video and F8 AF aside, the two reasons I find the II better than I are
1 - flicker detection. I shoot sport at 75% of the time. Indoor that would be mainly hockey, boxing and basketball and have to deal with flicker a bit. Before 1DX I didn't even know about flicker, I just hated fixing every photo individually. The worst thing is to get your best shot under worst quality: noisier, darker and more orange.
I did a test by shooting a hockey game with 1DX during the 1st quarter and the other two with the 1DX II and I ended up not taking any shot from the 1st quarter. 1DX II snaps faster, tracks better, but most of all a lot easier to handle in post. If I shoot JPG then I wouldn't see much of difference in terms of noise between the brightest shots on the 1DX vs the 1DX II, but big difference when taking the worst quality due to flicker. If I shoot raw then the 1DX II is 1 stop better, due to the fact that it retains better detail in the dark areas (and it is not just because people say so), and when you take the photos in ACR and drag the shadow and black sliders to the right you do not destroy the photo as fast as with the 1DX. In fact, with the 1DX I had to overexpose my photos a bit to avoid these color noise in darker area, but in the 1DX II I actually under expose them and then brighten them up in post. The post is a lot easier and if you shot in the same arena you keep the same setting for all of your photos the season long.
For the same arena, I shot only with 70-200 2.8 with the 1DX, while on the 1DX II I shoot with 100-400 II, thanks to the anti-flicker and less noise in the dark.
Cannot give you photos due contract with the arena. You will have to take my word for it.
The other feature is focus. I shoot portraiture and lifestyle as the 25% remaining. Outdoor, I usually put my subject under shade or, if I have no choice, backlight under the sun. The 1DX has more trouble focusing in back lighting, or subject in shade with bright background. With the 1DX II, I can snap in a Youngnuo flash trigger for the assist beam, when shooting with viewfinder, or lately more and more in live view. Backlighting with live view is fantastic - I really love it. When the 1DX II has trouble recognizing the face, just move close to the subject so that the face almost occupies the view, once the 1DX II recognizes it then back to where you want to shoot. I have never missed a focus at 85mm 1.4; it used to be my nightmare with the 1DX using focus and recompose - I had to shoot multiple time to make sure.
I think, Canon should upgrade the feature, so that when the face has some stuff on it (like mask or some hats) and the camera doesn't recognize it, we should have an option to tell the camera that this is a face and find the eyes to focus on.
As I said, in my early post, moving subject has to be shot with viewfinder. I wish they upgrade and fix the lack of continuous focus in live view, if possible, in next firmware.