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.
See our Canon EOS-1D Mark II studio test on page 2
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.
Go to full screen mode
Raw DR: Exposure Latitude
Image comparison tool
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Image size:
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Download: JPEG (8.9MB), RAW (19.4MB)
Download: JPEG (19.7MB), RAW (81.6MB)
Download: JPEG (10.8MB), RAW (18.8MB)
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.
Go to full screen mode
Raw DR: ISO-invariance
Image comparison tool
|
Image size:
|
Download: JPEG (9.8MB), RAW (25.9MB)
Download: JPEG (15.4MB), RAW (18.1MB)
Download: JPEG (10.6MB), RAW (19.0MB)
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.
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