Review by Klaus Schroiff, published September 2015

Introduction

As of the time of this article, it's the only native prime lens of the system. However, it is a fairly interesting one. First of all it's a pancake lens thus about as small as it gets but despite the small size it is still pretty fast. Unlike its cousins (Canon EF-S 24mm f/2.8 STM (APS-C) and EF 40mm f/2.8 STM (Full Format)), it sticks to the field of view of a classic "35mm" lens (22mm * 1.6x) so it's still wide enough for many applications - especially street photography. The combo with the Canon EOS M3 is also super compact making it a take-me-everywhere option - almost at least.

The build quality of this little Canon lens is pretty good which also originates in the simple fact that there aren't many moving parts in the first place. The lens consists of a mixed plastic/metal body based on a metal mount. The tiny focus ring operates smoothly. The length of the lens (inner tube) changes a tiny bit during focusing operations. It's also worth to note that the front element of the lens is surprisingly small despite the comparatively large max. aperture.

Just like other mirrorless systems, Canon EOS M uses a stepping motor (STM) for focus operations. This works noiselessly and reasonably fast although it stays short of the best competitors here. Manual focusing works "by-wire" thus you actually drive the AF motor by turning the focus ring. This works nicely and it's very precise actually.

The product images provide a comparison of the EF-M 22mm f/2 STM (left) to the EF-S 24mm f/2.8 STM (for APS-C EOS DSLRs). You may debate whether the difference in size is significant (percentage-wise that is) but remember that the EF-M lens is a full stop faster and a bit wider!