Image Quality

You'll get tack sharp imagery from the Canon RF 85mm F1.2L, with pleasing bokeh and no color fringing in high contrast, out-of-focus regions. Cat's eye bokeh is visible at the widest apertures.

Key Takeaways:

  • Superb sharpness at F1.2 across the frame
  • The lens reaches peak central sharpness at F2 on a 30MP EOS R
  • No color fringing or longitudinal chromatic aberration thanks to 'BR optics' element
  • Generally smooth bokeh balls that are largely free of patterning or color fringing, though 'cat’s eye' bokeh is apparent at F1.2 and smaller balls can be a little hard-edged
  • Essentially free of curvilinear distortion
  • Vignetting is low overall and absent from real-world images from around F1.8 onwards

The good news – and there’s plenty of it, but this is really where it shines – is that sharpness is already superb at F1.2, right up to the edges of the frame. What’s just as impressive is that corner sharpness is pretty much just as strong here, with just the smallest of dips if you’re really looking for it. This is maintained very well as you close down the aperture, and things are rosy until around F11, where diffraction induced softness starts to be noticeable on the 30MP EOS R, reducing resolution across the frame. In terms of sharpness and consistency across most commonly used aperture settings, this is a remarkable performance.

Out-of-focus areas are rendered beautifully at the widest apertures, with a gentle roll-off from focused areas and a heavy creaminess at their most blurred. Cat’s-eye bokeh can be very apparent at the widest aperture, not only at the edges but also just away from the centre of the frame (see image at top of page). Thankfully, bokeh is largely free from any texture. There is some, but it’s only really apparent in darker examples – and bokeh balls are nice and round in the center of the frame, with a natural shape maintained until around F1.8 or so in most scenes. A couple more aperture blades would help to retain perfect the roundness of the aperture, which is lost from F2 onwards.

Bokeh is very pleasing, with little to no texture, onion rings, or color fringing in out-of-focus highlights. Highlights remain perfectly round until F2, after which you'll see some shape due to the aperture blades. There's not much cat's eye bokeh from F2 onward to smaller apertures.

Out of focus highlights can have a slight bright edge, particularly as you stop down a little, which you can see in some of the bokeh discs above and here. It's not to a degree we would ever complain about, but if you're looking for even smoother, more 'Gaussian' bokeh, Canon makes a 'DS' variant of the lens which, like lenses from Sony and Fujifilm that use apodization elements, is designed to deliver smoother bokeh balls but at the expense of some light transmission. Out of focus highlights with the DS variant won't have as pronounced edges but, instead, gradually darkening circles as you go outward from center. While this can lead to smoother overall bokeh, some photographers actually prefer the well-defined bokeh discs, and increased background blur traditional, non DS, lenses produce.

Part of the reason for the well-defined bokeh discs is how much Canon’s lens designers have sought to reduce longitudinal chromatic aberration (LoCA); and it shows. Wide-aperture primes such as this one are often troubled by LoCA, but it’s simply not an issue here. The worst of this only ever manifests as very faint traces in typically problematic scenes, but even here it’s low enough for it not to matter, or even be noticed at all. Lateral chromatic aberration is also not an issue at all: and even if it were it’s likely the in-camera correction would be able to handle that.

At its very worst, wide open, there’s around 1.5-2 stops of vignetting in the corners of the frame, although this level is confined to the extreme corners, with the vignetting that leads up to it being far less pronounced. Things improve significantly at F1.4, and once again at F1.6, and by F1.8 you’re unlikely to notice it in everyday images. Frankly, even at F1.4, vignetting is barely a factor in many real-world images. If you do object to it, you’ll find the camera’s Peripheral Illumination Correction function lifts this away quite effectively.

Little to no curvilinear distortion.

Distortion is also essentially absent, even when capturing subjects with perfectly linear details across the frame. Users of Camera Raw or Lightroom can call on the profile built into the most recent version of the software, but the changes made are nothing beyond a light lifting of vignetting and the smallest of corrections over barrel distortion.

The combination of coatings inside the lens means that it’s generally well proofed against flare and ghosting in general use, even without the supplied hood. Contrast remains very good in the sorts of images where you might be cautious to use the hood, and even when flare starts to creep into the frame the image holds up well. It’s also possible to get decent sunstars from the lens, but given the longer focal length, it's not always easy to get clean and defined ones.

There's almost no color fringing to speak of, thanks to Canon's BR Optics element that minimizes longitudinal chromatic aberration. You'll want to be careful about using electronic first curtain shutter with fast shutter speeds wide open, though, which led to the truncated bokeh discs here.

An important consideration when shooting with such a fast aperture lens on Canon's mirrorless bodies is the effect of the electronic first curtain. At fast shutter speeds (above 1/1000s), wider aperture settings will lead to truncated bokeh discs as you can see in the image above. Not only does this lead to displeasing out-of-focus highlights, but bokeh in general will be less pleasing, with out of focus areas looking like the image was shot with a smaller aperture. At these fast shutter speed / aperture combinations, you'll want to disengage electronic first curtain shutter and revert to a fully mechanical shutter. It's unfortunate that Canon does not automatically do this, as it's a nuisance for the photographer to have to remember to change such esoteric, technical settings just to get the full benefit of such bright lenses.

An additional thing to bear in mind is that neither the EOS R nor the EOS RP’s electronic shutter offers any shutter speeds higher than that allowed by the mechanical shutter (and the EOS RP’s is buried within a scene mode). That means you may run into difficulties when using the lens at its widest few apertures in bright light, as I often did during this review. Those drawn to the DS variant of the lens, however, may find the 1.5-stop reduction in light transmission is enough to offset that.

While the lens’s performance on an EOS R is highly impressive, the same caveat applies here as it does to all RF lenses right now: We don’t know how it will behave on a body with more than 30MP. Such a high standard of performance suggests that the lens will continue to shine on a future body that incorporates a more punishing sensor, though we won’t know that for sure until such a camera materializes.

vs. EF 85mm F1.4L IS USM

For those curious about how the RF 85mm stacks up against the EF version, which you may already own, we've shot the lenses side-by-side in a controlled studio environment so you can take a look at sharpness, bokeh, and color fringing characteristics between these two lenses.

First, the RF 85L appears to be sharper than the EF version wide open. The RF 85L reaches peak sharpness by around F2, which is impressive for such a fast prime. In comparison, the EF 85L reaches its peak sharpness at F2.8.

Wide open sharpness on the RF 85L appears very impressive vs. peak sharpness of the lens, so photographers should have no qualms about sacrificing sharpness when shooting wide open. Compare this to the disparity between wide open and peak sharpness on the EF version. Canon is putting some serious prowess into its RF lens lineup.

As we've seen throughout all of our samples, longitudinal chromatic aberration, which typically shows up as purple and green fringing in front of, and behind, the focal plane is simply not an issue at all with the RF 85L, thanks to its 'BR optics' element. Meanwhile, you can see some green fringing in the edges of out-of-focus highlights on the EF 85L, meaning you can expect to see some color fringing in out-of-focus high contrast regions with the EF lens. The presence of longitudinal chromatic aberration on the EF lens no doubt impacts its peak sharpness performance wide open, which is likely why it falls behind the razor-sharp imagery the RF 85L provides.

Finally, optical vignetting, which causes the cat's eye effect, is mostly gone by F1.8 on the RF 85L, and by F2 on the EF 85L, as you can see by comparing out-of-focus bokeh discs here.