The Canon RF 28mm f2.8 is the slimmest lens for the EOS R system to date. Announced in May 2023, the RF 28mm is a wide-angle prime designed for EOS R mirrorless bodies only. 

Mount it on a full-frame body like the R8, R6 or R5 and it’ll deliver mild wide-angle coverage, while fitting it on a cropped body with an APSC sensor like the R100, R50, R10 or R7 will reduce the coverage to 45mm, turning it into a standard lens.

Measuring 69mm in diameter, just 25mm long, and weighing a mere 120g, the RF 28 becomes one of the smallest and lightest lenses in the system to date, a true pancake lens which transforms the portability of any body you mount it on.

Here’s the RF 28 on the R100 body launched alongside it, making an impressively compact combo weighing less than half a kilo.

Given the size, it’s not surprising to only find one ring, and a slim one at that, performing double-duty as manual focus and RF control, with a switch to choose between those functions.

As a lower-priced lens, it’s not weather-sealed, although it does at least have a metal lens mount, while at the other end is a 55mm filter thread. 

Focusing is performed by an STM motor which mildly extends the barrel in use. The closest focusing distance is 23cm, resulting in 0.17x magnification.

In order to achieve the compact size, Canon’s employed some innovative non-circular elements in the rear with a complex profile that resembles a seagull with outstretched wings, or perhaps an elaborate moustache.

It’ll be interesting to see how it compares to Canon’s other pancake lenses including the EF-S 24mm f2.8 and EF 40mm f2.8, both of which can be snapped up at a lower price, but losing some of their compact charm when mounted on a mirrorless camera with an adapter. Or there’s the EF-M 22mm f2, again at a lower price, albeit only for the EOS M system. 

The bottom line though will be the performance of the RF 28 in practice, and once I’ve tested a final production sample I’ll update this page.