Canon RF 85mm f/1.2L USM DS Review
The RF 85mm f/1.2L USM DS is a very fast short telephoto prime lens for the Canon EOS R full-frame mirrorless camera system.
It's completely identical to the standard RF 85mm f/1.2L USM lens, with the exception of a special DS (Defocus Smoothing) vapor-deposited coating that has been applied on the front and rear surfaces of the lens to soften and smooth the bokeh quality. This effect is especially apparent when shooting wide-open at f/1.2, becoming gradually less pronounced as you stop-down the lens.
The main trade-off is that the DS coating restricts the amount of light that passes through the lens to the image sensor, so much so that when shooting at f/1.2, the brightness of the lens is effectively 1 1/3 stops darker than on the standard RF 85mm optic, being equal to a T-stop of T2.2. This means that that you have to either choose a slower shutter speed or increase the ISO speed to compensate for the loss of light.
As with its slightly cheaper sibling, the Canon RF 85mm f/1.2L USM DS lens features a bright f/1.2 maximum aperture, a ring-type UltraSonic Motor (USM) AF system more usually found in Canon’s super telephoto lenses which delivers fast, near-silent autofocusing, 9 rounded diaphragm blades for smoother bokeh, 85cm close-focus distance, a configurable control ring, and a weather-resistant construction.
The Canon RF 85mm f/1.2L USM DS is priced at £3,249.99 / €3799.99 / $2999.00 in the UK, Europe and the USA respectively.
Ease of Use
With the only difference between this lens and the standard RF 85mm f/1.2L USM being the Defocus Smoothing coating, everything that we said about the non-DS version applies equally to the DS version.
There's no getting away from the very obvious fact that the Canon RF 85mm f/1.2L USM DS is a massive prime lens, weighing in at 1195g and measuring almost 12cm in length, making it slightly longer and heavier than the equivalent Canon EF 85mm f/1.2L USM DSLR lens (although you have to factor in the extra size, weight and cost of an adapter if you want to use that lens on an EOS R series camera).
When mounted on the Canon EOS RP mirrorless camera that Canon sent us for testing, the Canon RF 85mm f/1.2L USM DS feels very front heavy indeed, requiring you to cradle it with your left hand. One-handed use isn't really possible.
Build quality is simply outstanding. The Canon RF 85mm f/1.2L USM DS feels very solid in your hand, and it features an L-series level weather-resistant design that protects against dust and moisture.
A new feature for certain RF lenses is the Lens Control Ring at the end of the lens barrel, which can be used to control certain key camera settings (TV, AV, ISO and exposure settings). Although not a new idea in the wider photography world, this is the first time that Canon have incorporated this idea into their interchangeable lenses.
The Canon RF 85mm f/1.2L USM DS does not feature Image Stabilisation, so there's no control on the lens for this feature. With the current EOS R bodies also not offering IBIS, you have to be more careful with your hand-holding technique to ensure optimum sharpness.
There is a focus mode switch with the usual AF/MF settings. Note that this lens usefully offers full-time manual focusing even when AF is selected.
There's also a focus limiter switch that toggles between Full and 1.5m-Infinity settings to help speed-up the auto-focusing system when required.
The Canon RF 85mm f/1.2L USM DS lens has a generously sized focus ring with a ridged, rubberised grip band. There are no hard stops at either ends of the range, making it more difficult to set focus at infinity.
Polariser users should be pleased that the large 82mm filter thread doesn't rotate on focus.
When it comes to auto-focusing, the Canon RF 85mm f/1.2L USM DS zoom is a pretty quick performer considering just how much glass is inside it, taking around 0.15 seconds to lock onto the subject when mounted on the Canon EOS RP camera that we tested it with.
We didn't experience too much "hunting" at all, either in good or bad light, with the lens accurately focusing virtually all of the time, thanks to the superb low-light capabilities of the EOS R cameras (down to -6EV (EOS R) and -5EV (EOS RP).
The USM motor is very quiet, which makes this lens well-suited to video recording, except when focusing from near-to-far, during which an audible whirr is present.
The lens ships with a large round lens hood (ET-89) with a lock button and a soft case (LP1424).
At the 85mm focal length the angle of view is 24 degrees.
Chromatic aberrations, typically seen as purple or blue fringes along contrasty edges, are very well controlled with this lens, so much so that we could only find a few very minor examples in our test shots.
The Canon RF 85mm f/1.2L USM DS produces fairly nice sunstars when stopped-down to f/16 or f/22, although be careful to watch out for flare effects when shooting directly into the sun.
Vignetting and Distortion
When using the lens wide-open at f/1.2, you can see some light fall-off in the corners. Stopping down helps, although to completely get rid of this phenomenon, you will need to use an f-stop of f/2.8 or smaller. Distortion is very well controlled.
The Canon RF 85mm f/1.2L USM DS isn't really a macro lens. The close-focus point is at 85cm from the film/sensor plane and Canon quotes a maximum reproduction ratio of 0.12x. The following example illustrates how close you can get to the subject.
Bokeh is a word used for the out-of-focus areas of a photograph, and is usually described in qualitative terms, such as smooth / creamy / harsh etc.
In addition to employing an iris diaphragm with nine rounded blades on the RF 85mm f/1.2L USM DS, Canon have also applied a special DS (Defocus Smoothing) vapor-deposited coating that smooths out the outline of the bokeh, creating a much softer effect than can be achieved with the standard RF 85mm f/1.2L USM lens.
Whether or not you prefer this softer effect is very much a personal choice, but at least Canon are giving you the option, albeit at an even higher price-point and with the effective loss of light that you'll need to comensate for.
Below you'll find some examples, and you are also encouraged to check out our sample images.
In order to show you how sharp this lens is, we are providing 100% crops on the following page.