Canon RF 35mm f/1.8 IS Macro STM Review
The RF 35mm f/1.8 IS Macro STM is a versatile moderate-wide-angle prime lens for Canon's new full-frame mirrorless camera system.
Featuring a 1:2 macro design with a minimum focusing distance of 17cm, STM stepping motor for smooth, precise and quiet continuous auto-focusing, Super Spectra coating on the lens elements to minimize ghosting and flare, 9 rounded diaphragm blades for smoother bokeh, and image stabilisation offering a claimed 5-stop advantage, the Canon RF 35mm f/1.8 IS Macro STM is a capable all-rounder.
The Canon RF 35mm f/1.8 IS Macro STM officially retails for £519 / €519 / $499 in the UK, Europe and the USA respectively, making it the cheapest RF lens available at the launch of the Canon EOS R system.
Ease of Use
The Canon RF 35mm f/1.8 IS Macro STM is a pretty small and compact prime lens, weighing in at 305g and measuring 6.3cm in length, which is very similar to the Canon EF 35mm f/2 IS USM DSLR lens.
It's also by far the smallest lens in the fledgling RF range, being dwarfed by the 24-105mm f/4 kit zoom and especially the 50mm f/1.2 and 24-70mm f/2 lenses.
Build quality is very good. The Canon RF 35mm f/1.8 IS Macro STM feels solid in your hand, even if it is mostly made out of plastic, and it features enhanced resistance to shock and vibration too.
A new feature for RF lenses is the Lens Control Ring at the end of the lens barrel, which can be used to control certain key camera 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 35mm f/1.8 IS Macro STM boasts Image Stabilisation which Canon claims offers an advantage of up to 5 f-stops over lenses without a stabilizer. This is activated via the Stabilizer On/Off switch on the side of the lens. If the camera body supports it, Canon's IS technology is also able to detect intentional panning movement and automatically switch from the Normal IS mode to the Panning IS mode.
The final control on the lens barrel 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.
The Canon RF 35mm f/1.8 IS Macro STM lens has a fairly narrow focus ring with a ridged, rubberised grip band. There are no hard stops at both ends of the range, making it more difficult to set focus at infinity. Polariser users should be pleased that the 52mm filter thread doesn't rotate on focus.
When it comes to auto-focusing, the Canon RF 35mm f/1.8 IS Macro STM zoom is a quick performer, taking around 0.10 seconds to lock onto the subject when mounted on the Canon EOS R camera that we tested it with.
We didn't experience very much "hunting" at all, either in good or bad light, with the lens accurately focusing virtually all of the time. Being an STM lens, it has a stepper motor - designed for quick, quiet and smooth autofocus - something which videographers may find particularly appealing, which makes this lens well-suited to video recording.
The lens does not ship with either a hood or a soft case.
At the 35mm focal length the angle of view is 63 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 minor examples in our test shots.
The Canon RF 35mm f/1.8 IS Macro STM produces quite nice sunstars when stopped-down to f/16 or f/22.
Vignetting and Distortion
With the lens wide open, you can see some obvious 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/4 or smaller. Barrel distortion is also fairly evident in this shot.
The Canon RF 35mm f/1.8 IS Macro STM doubles up as a very competent macro lens. The close-focus point is at 17cm from the film/sensor plane, and Canon quotes a maximum reproduction ratio of 0.5x. The following examples illustrate how close you can get to the subject and the kind of bokeh effects that can be created.
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. Canon have employed an iris diaphragm with nine rounded blades for a pleasing rendering of the out-of-focus highlights. Based on what we have seen, we can say that they have largely succeeded. Below you'll find some examples, but 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.