The first High ISO test was done by Xerodigital and Now its time for (non-english website) focus-numerique, during the test 1DX performance was better than the D4, Canon images are usable up to IS 12800, Nikon D4 is limited to ISO 6400. The scene is illuminated at 200 lux, the Canon EOS-1D was at 1/4 s, f / 5.6 & ISO 100.
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You can also compare images from the Canon 1D X with those of the Nikon D4 16 MP. So who is the winner of this clash of the titans? Overall, the Canon to the housing pro Nikon with better grain content (it is almost invisible at ISO 6400). D4 is already showing its limits to ISO 6400, sensitive to the 1D X which seems to be very comfortable. In 12800, the red mark still dominates its rival will not return the head to ISO 25600.
Full test samples available for download / see the full review here (Translated bu google)
See More Canon 1DX vs. Nikon D4 Specification Comparison Review
I have been a Nikon user my entire life……and always wanted to make the next step to a Nikon pro body full frame camera (currently the D4). But the more I read and when I look at results like this, Canon has me thinking about that decision. The big draw back to making the switch (of course) is my investment in the Nikon high end glass. To convert everything from Nikon to Canon would be a $25,000 to $30,000 investment……not just the cost of the new full frame body. But I am convinced that at least for now, Canon seems to have the edge for High ISO quality……and considering I do a lot of indoor sports photography in who knows what kind of lighting conditions……..this IS a serious concern to me.