Dynamic Range

While the image above looks pleasing at this viewing size, click on it to view at 100% and the noise in the shadows is immediately obvious. Processed in Adobe Camera Raw 11.
ISO 100 | 1/400 sec | F16 | Canon RF 24-105mm F4L
Photo by Richard Butler

The EOS R, with a sensor closely related to that of the EOS 5D Mark IV, performs very similarly to that camera, but with very slight differences appearing at higher ISOs and when files are pushed.

Key takeaways:

  • Dynamic range is, for most purposes, broadly similar to the EOS 5D Mark IV
  • While there's little to no striping or banding visible, the EOS R's files are slightly noisier than its DSLR cousin
  • Overall, dynamic range is good, but trails most current full-frame cameras on the market.

Dynamic range is the range of tonal values that a camera can represent, from the brightest recorded tone to the darkest usable value. There is, of course, an element of personal taste to this.

Rather than just quoting numbers, we try to show the photographic impact. We do this in two ways: first, our Exposure Latitude test shows the effect of lifting the shadows of images shot with increasingly low exposure (as you would if you were trying to capture/retain more highlight information).

However, reducing the exposure increases the noise level, which makes it difficult to tell what's happening at the sensor level. This is where our 'ISO Invariance' test comes in. Here we shoot different ISO settings using the same exposure values. This means that any difference in noise must come from the camera. Between the two tests, we can see how tolerant the camera's files are to having addition tonal information pulled up from the shadows into the visible parts of the image.

Exposure latitude

Here, you can see from comparable pushes of EOS R compared to EOS 5D Mark IV files that they're very similar, with the EOS R appearing ever-so-slightly noisier. This is something we've confirmed quantitatively from our collaboration with Bill Claff. This places its performance behind two competing cameras from Sony and Nikon, but ahead of Canon's own EOS 6D Mark II.

Moving beyond a 4EV push, we can see the Sony and Nikon continuing to perform ahead of their Canon peers, which begin to show color blotching. But pushed far enough, the Nikon Z6 will show banding, which is also visible when downscaled to smaller resolutions.

ISO invariance

Like the 5D Mark IV, the EOS R isn't entirely ISO-invariant. Pushing underexposed ISO 100 and ISO 200 shots by 6 and 5 stops in post-processing, respectively, yields higher noise levels than a native ISO 6400 exposure. However, by ISO 400 and above, the camera does for the most part exhibit ISO invariance. This means you can underexpose a traditional ISO 6400 exposure by 4 EV by shooting it at ISO 400, and then raise exposure by 4 EV in post with little noise penalty. But crucially, you'll have saved 4 EV of highlights that you'd lose by shooting at ISO 6400.

Compared with Canon's EOS 6D Mark II, the EOS R turns in a better performance. But the newest chips from the Sony a7 III and Nikon Z6 fare better, but again, the latter may exhibit banding in more extreme pushes.