The RF 35mm F1.8 IS STM is one of four lenses announced alongside the Canon EOS R, the first camera in the company’s new EOS R mirrorless system.

Something of an odd one out in that quartet, it’s the only non L-series lens released for the RF line to date, although that will soon change with the arrival of the RF 24-240mm F4-6.3 IS USM later this year. It’s also around half the price of the next cheapest lens in the system, while its focal length and aperture, combined with the fact that it’s a prime lens, also allow it to be considerably smaller and lighter than every other option so far. All of this should mean it holds particular appeal for EOS RP owners who’d like to start exploring the native lens selection but find their camera bodies – and/or wallets – overwhelmed by the other current native offerings.

A 35mm F1.8 option is a fairly sensible and versatile lens to have at the start of a system, and its broad appeal should pique the interest of street, travel, nature, portraiture and even landscape photographers. The added bonus of image stabilization also makes the absence of sensor-based stabilization from the current bodies less of an issue, while ‘Macro’ in the name indicates a close focusing distance of 17cm / 6.7 in (albeit shy of being truly macro, offering a maximum reproduction ratio of 1:2).

All pictures by Matt Golowczynski unless otherwise noted.

Key Specifications:

  • Focal length: 35mm
  • Aperture range: F1.8-22 (In 1/3EV stops)
  • Filter thread: 52mm
  • Close focus: 0.17m (0.56ft / 6.7in)
  • Maximum magnification: 0.5x
  • Diaphragm blades: 9
  • Hood: EW-52 (optional)
  • Length / Diameter: approx. 74.4 x 62.8mm (2.93 x 2.47in)
  • Weight: approx. 305g (approx. 10.8 oz.)
  • Optical construction: 11 elements in 9 groups

The lens has a new formula that sees 11 elements arranged in nine groups. This includes a single glass moulded aspherical element within the focusing group in the middle of the formula, which is in place both to combat spherical aberration and also to keep image quality consistent over focusing distances.

With the lens mounted on either the EOS R or EOS RP, you have access to Canon’s full suite of aberration-rectifying options that deal with vignetting, lateral chromatic aberration, distortion and diffraction, in addition to the Digital Lens Optimizer that aims to counter the softening effects from diffraction, among other things.

The optical design of the RF 35mm F1.8 Macro is similar to the older EF 35mm F2, but flipped. Whereas the older optic (designed for DSLRs) has a large front element and a small rear element, the RF 35mm F1.8 (designed for mirrorless) has a small front element and a large rear element.

Canon has pointed out how the RF mount’s width and the short flange back distance gives new freedom to lens designers, and the optical design here – or, more specifically, the way in which this differs from existing designs in similar lenses – appears to back that up. The rearmost element sits very close to the back of the lens itself and is the largest in the array. Canon claims that this is one of the key reasons for the high corner-to-corner sharpness, even when the lens is used wide open. A diagram of the optical construction also shows that the aperture diaphragm is positioned relatively close towards the front of the lens, which is said to be one reason why the lens can offer such a wide aperture without compromising on size.

The diaphragm is made up of nine blades, which bodes well for round bokeh, while the minimum focusing distance of 17cm gives a minimum working distance – i.e. the distance from the front of the lens to the subject – of 7cm.

A hood isn’t provided with the lens as standard, and that may well be explained by the likelihood of the average user needing or wanting to use it with such an optic. Still, for this kind of money it's a bit disappointing not to have a hood included.

Design and Handling

Not only is this is the lightest and most compact RF lens so far, but the roadmap Canon unveiled towards the start of the year suggests that will remain so for a while. It’s 30g lighter than the existing EF 35mm F2 IS USM and just a fraction wider, but 70g lighter and considerably shorter in length than the Nikon Z 35mm F1.8. Unlike the latter lens, however, this one isn’t weather sealed.

The lens balances very nicely on the EOS R body and is light enough to allow for one-handed operation when required. Two large switches on the barrel provide control over focus mode and image stabilization, and these click between positions positively. They also barely protrude from the casing, which makes it difficult to inadvertently knock them out of place.

The outer barrel’s matte gray finish mirrors that of the EOS R body, as does the silvery rear of the inner lens barrel with the host cameras throat. The mount is metal and build quality overall appears to be perfectly good.

The lens is encircled by a Control Ring towards its front and a focusing ring towards the middle of the barrel. While the pair sit close to each other, their different finish, together with the fact that the Control Ring is clickable, mean you’re unlikely to mistake them in use.

You can customize the action performed by the Control Ring to your liking, or even deactivate it completely if that suits you, and it’s also possible to switch the direction of rotation if the default arrangement bothers you. If enabled, you can opt for it adjust aperture, shutter speed, ISO or exposure compensation, and in each case you can select whether the ring adjusts these at all times or only when you have your finger half-pressed on the shutter release button. The setting you select stays the same between exposure modes, which you probably won’t find to be an issue unless you tend to hop between exposure modes with some frequency.

Some predictable limitations occur with some combinations or setting and exposure mode, such as no exposure compensation control in manual mode, and no adjustment of aperture in shutter priority mode (and vice-versa).

The Control Ring provides excellent feedback, with increments nice and coarse, and the camera responds without any delay. Those looking to use the lens for video might be disheartened to learn there’s no way to alternate be-tween clicked and de-clicked operation, but if you’re happy with it being permanently de-clicked, Canon can do this for you (for a fee).