Announced back in February, the Canon EOS-1D X Mark II has at long last made its way through our door. We're just itching to get it out and put its 20.2MP sensor and 14 fps burst rate to work shooting some fast action to see what its AF system can do, but first we put it through our slate of studio image quality tests.

Like the EOS 80D there's a big improvement in the camera's dynamic range. Canon's move to a design using on-chip analog-to-digital conversion ensures less noise is added before the signal is converted into digital values, meaning it's easier to distinguish between captured information and background noise. In turn, this means more malleable Raw files with more useful information available when you try to process them.

In our standard studio tests, the findings were slightly less positive. The JPEG engine seems to use the same sharpening parameters as the 50MP EOS 5DS R, which ends up being rather heavy-handed when applied to 20MP levels of detail capture. High ISO performance, once a Canon strength, drops a little behind its better rivals.

Raw Dynamic Range

Exposure Latitude

In this test we look to see how tolerant of pushing exposure the EOS-1D X II's Raw files are. We've done this by exposing our scene with increasingly lower exposures, then pushed them back to the correct brightness using Adobe Camera Raw. Examining what happens in the shadows allows you to assess the exposure latitude (essentially the dynamic range) of the Raw files.

Because the changes in this test noise are primarily caused by shot noise and this is mainly determined by the amount of light the camera has had access to, the results are only directly comparable between cameras of the same sensor size. However, this will also be the case in real-world shooting if you're limited by what shutter speed you can keep steady, so this test gives you an idea of the amount of processing latitude different formats give.

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.

ISO Invariance

A camera with a very low noise floor is able to capture a large amount of dynamic range, since it add very little noise to the detail captured in the shadow regions of the image. This has an interesting implication: it minimizes the need to amplify the sensor's signal in order to keep it above that noise floor (which is what ISO amplification conventionally does). This provides an alternate way of working in situations that would traditionally demand higher ISO settings.

Here we've done something that may seem counter-intuitive: we've used the same aperture and shutter speed at different ISO settings to see how much difference there is between shooting at a particular ISO setting (and using hardware amplification) vs. digitally correcting the brightness, later. This has the advantage that all the shots should exhibit the same shot noise and any differences must have been contributed by the camera's circuitry.

You can see the EOS-1D X II's full results here. As you may have inferred from the Exposure Latitude tests, the EOS-1D X II isn't entirely ISO invariant - the camera is adding enough downstream read noise such that you can't use a lower-than-normal ISO and selectively brighten the image later - to protect highlight information - without some noise cost.

To put this in perspective, though, the camera's files appear much more flexible than those of the Canon EOS 5DS R, which itself was a big step forward from the EOS 5D Mark III. So, while they're not a match for the likes of the Nikon D750 or the latest Sony sensors, the 1D X II is a step forward for Canon, and performs better than the Nikon D5 in this regard. In fact this test slightly under-represents the Canon's performance, since the D5's ISO 6400 result is better to start off with: to start off ahead but then fall behind the Canon, the Nikon must be adding more noise at low ISOs.