Dynamic range

The EOS R5 is more than capable of handling very high-contrast scenes.

Key takeaways:

  • Impressive, though not class-leading, dynamic range when using mechanical shutter
  • Using the silent electronic shutter drops the camera's readout to 12-bit, and so you may notice more shadow noise in those images if you're performing extreme adjustments.

ISO invariance

Our ISO Invariance looks at images shot with the same exposure settings but different ISO settings. This lets us see how much electronic (read) noise there is that can be overcome using amplification.

When using the fully mechanical or electronic first-curtain shutters, the R5's performance is quite good. It's also the first Canon sensor we've encountered that uses a dual-gain design that kicks in at ISO 400, which helps explain that the ISO 400 and ISO 6400 shots are essentially the same.

Why does this matter? Because it tells us how well-designed the sensor is, and this performance can then be exploited. For instance, in low light situations, you can use the shutter speed and aperture settings of a high ISO exposure, but keep the camera set to ISO 400. By the time you brighten up the shot in post, the image won't be noticeably noisier than if you shot natively at a higher ISO, but you've saved several stops of highlight information. This is great for keeping, say, neon lights from clipping to white in a street photo at night.

Compared to its peers, the EOS R5 falls somewhat in the middle of the pack, besting the Panasonic S1R but coming in behind Sony's a7R IV and Nikon's Z7.

The EOS R5 also has a fully electronic shutter option, which drops the camera to 12-bit readout mode. This keeps rolling shutter largely at bay, but results in increased noise in the very deepest shadow regions. You probably won't notice it over ISO 400, though. In other words, for the highest dynamic range scenes, stick to a low ISO and the mechanical shutter. For low light scenes, the use of the electronic shutter is less critical, though watch for banding under artificial light.

Exposure latitude

Our Exposure Latitude test does what you might be temped to do in bright light: reduce the exposure to capture additional highlights, then brighten the shadows. This is analogous to what Highlight Tone Priority mode does in bright light conditions.

Again, the EOS R5 turns in a really good performance here, actually looking slightly better to our eyes than the Sony. However, we do think you'd be hard-pressed to find a difference between them in real-world images. But as we'll discuss below, the Canon is employing some noise reduction to get these results.

But, as before, switch to the electronic shutter and things take a turn for the worse. That said, it's not super noticeable until you get into the very deepest shadows.

Noise reduction

It's also worth pointing out that, as with the EOS R6, it looks like detail smears a little if you look into the deepest shadows, indicative of some degree of noise reduction in the Raw files.

Here are our ISO 6400 and ISO 100 + 6EV images from the ISO Invariance test, reprocessed with noise reduction minimized:

There's a noticeable loss of low-contrast detail in the brightened ISO 100 image (more so than we would expect even with the exposure boosting), so your practical dynamic range will be impacted by both sensor performance and this noise reduction.

HEIF HDR images

The EOS R5, like the R6 and EOS-1D X Mark III, can natively capture High Dynamic Range (HDR) images in the HEIF format, using the 'PQ' standard. This isn't the same as the 'overly HDR' images of yesteryear; these images are intended to be viewed on compatible screens that offer a broader range of brightness than is possible with standard screens. (Read our article about True HDR images here)

As of this writing, you can convert HEIF files to JPEG in Canon's Digital Photo Professional software as well as in-camera. At the time of this writing, neither option gives you any control whatsoever over the process, but doing so gives you a noticeably different result from a standard out-of-camera JPEG. See the below illustration from the Canon EOS-1D X III.

ISO 100 | 1/20 sec | F4 | EF 24-105mm F4L at 70mm | Photo by Dan Bracaglia

The R5 can also capture HDRTV-ready video, using the HDR PQ standard. In both stills and video, Canon recommends you use the Highlight Tone Priority mode which basically keeps the camera from clipping highlights to white by reducing the exposure or amplification to capture an additional stop of highlight detail that HDR TVs can display. The files still contain plenty of information in the shadows to be viewed on HDR compatible displays.

This is a necessarily limited representation of the difference between SDR and HDR images, constrained by your SDR display.

It's impossible for us to demonstrate the difference, as most people will be viewing this on an SDR display, but the distinction is that HDR HEIF files on and HDR display can show bright whites and darker blacks, and hence show the scene more realistically, but the HEIF converted down to an SDR JPEG, further up this page, shows the highlight regions getting darker (in order to squeeze the additional highlight tones into the SDR space), and the shadows are still clogged-up.