Canon EOS 1D X Mark II
The 1D X Mark I is the new Design & Build Quality Key Features
What was the need to include a CFast 2.0 card slot?
on the 1D X Mark I is
An important note for those who shoot 4K video with the 1D X II: This camera shoots 4K video at 4096x2160 pixels (known as DCI 4K), as opposed to UHD 4K which shoots 4K video at 3480x2160pixels. In other words, the 1DX Mark II provides extra pixels horizontally. Hence, if you intend to see the video on your TV, you should avoid framing anything too close to the edge of the frame, otherwise some portion of the frame may be cut out.