Raw Dynamic Range
The Canon EOS-1D X Mark II shows very similar amounts of noise to the excellent sensor in the Sony a7R II up until a 3EV push, with the Canon dropping behind after a 4EV push. It’s a similar story against the likes of the Nikon D750 or D810. This means that the darker shadows in a processed image would be slightly cleaner in images from these cameras, after contrast adjustments or a less extreme push.
However, this performance is noticeably better than the Canon EOS 5DS R and, significantly, better than the 1D X II’s most direct rival: the Nikon D5.
High ISO Performance
Although the 1D-X II shows significant increase in dynamic range at low ISOs in our dynamic range tests, high ISO Raw performance remains fairly similar to its predecessor, which is actually impressive considering the 1D-X II gains dual-pixel architecture for decisive video AF. Noise performance falls slightly behind the Nikon D5 (and even the Sony a7R II when normalized) at very high ISOs.
You can read the full Canon EOS-1D X Mark II studio tests at DPReview.
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