Canon EOS R5 II studio scene shows expected speed/DR tradeoff

Photo: Richard Butler

We’ve just received a reviewable Canon EOS R5 Mark II, so took it straight into our testing studio.

Our test scene is designed to simulate a variety of textures, colors and detail types you’ll encounter in the real world. It also has two illumination modes to see the effect of different lighting conditions.

The EOS R5 II gives very much the result you might expect: it’s essentially indistinguishable from its predecessor in terms of detail. It can’t quite match the resolving power of Sony’s 61MP a7R V, but it’s consistent with it most direct peer: the Nikon Z8.

The similarities persist as the light levels drop: at moderate ISOs it’s consistent both with its predecessor and its peers and perhaps a touch noisier at very high ISOs. Not enough that you’re ever likely to notice.

Dynamic range

In what’s becoming a familiar story, there appears to be a trade-off between speed and dynamic range on the EOS R5 II’s sensor. If you underexpose to protect highlights in your image, then try to make use of the shadows, by brightening them (which is the main mechanicsm by which you’re most likely to really push at the limits of a large sensor camera’s DR), you’ll find your shadows are noisier than those of the EOS R5.

And, comparing shots taken at the same exposure but differing ISOs, you can see that you need to apply more amplification to overcome this read noise, than you did with the original EOS R5. It’s not until you get to ISO 800 that the image starts to match the performance you get by shooting at ISO 6400, which suggests that, if this is a dual coversion gain design, it’s switching to its high gain mode at a higher ISO (The EOS R5 switched over at ISO 400).

Notably, there’s an appreciable noise cost to be paid for switching to electronic shutter mode, which means it’ll underperform the Nikon Z8 (at least in terms of DR) when used it its fast modes. That reduction in dynamic range doesn’t appear to be accompanied by a significant reduction in image quality in most tones of the images, though: even at high ISOs, the difference in most of the tonal range is marginal.