Canon EOS M3 – Focusing
Canon EOS M3, EF-M 18-55mm f/3.5-5.6 IS STM
The original EOS M’s biggest letdown was undoubtedly its autofocus system, which even after a major firmware update was disappointingly slow. Thankfully, the EOS M3 is much improved in this regard, at least with the 18-55mm kit zoom that I used for the majority of this test. While it doesn’t feel as snappy and decisive as the very best of its competitors, I found the AF to be fine for everyday shooting, at least with subjects that weren’t moving too quickly. It is also capable of tracking moving subjects to a degree, although the continuous shooting rate slows right down. Other recent cameras, such as the NX500 and Sony Alpha 5100, do much better in this respect.
The focus area can be selected from a 49-point (7×7) array covering most of the frame, and a face detection mode is also available. The AF area is quite large though, which can be a problem if you’re trying to focus precisely on a small subject. Sadly there’s no option to select a smaller focus point, unlike most other CSCs. In the example above the camera initially locked onto the background, and refused to refocus until I managed to reposition the AF point exactly to its liking.
Canon EOS M3, EF 70-300mm f/4-5.6 IS USM
Canon’s EF and EF-S-mount DSLR lenses can be used on the M3 via the EF-EOS M-mount adapter, complete with electronic aperture control, image stabilization and AF. In principle, the most recent STM lenses should autofocus perfectly well, but those with other types of focus motor might struggle. I tried this out with several older lenses, and while autofocus worked well enough for static subjects it was still very slow, taking a second or more to acquire focus. When a big shift of focus distance was necessary, the AF often hunted for a second or two and then just gave up. Some lenses did much better than others, although in a distinctly unpredictable fashion – for example, my old 50mm f/1.8 worked quite well, whereas my 24-105mm f/4 USM was slow and hesitant. The shot above was taken with the EF 70-300mm f/4-5.6 IS USM, which took a second or more to achieve focus.
This means that, in many cases, manual focus can often be quicker than autofocus. Yet while the EOS M has both magnified live view and a focus-peaking display, it stops fast lenses down automatically in bright light, which can result in inaccurate focusing at large apertures. You can get around this by assigning depth of field preview to the M-Fn button and holding it down during focusing, but this really shouldn’t be necessary.
Overall, I’d say that, while you can use your DSLR lenses on the EOS M, if you’re looking for a small camera to make the most of them, the EOD 100D is still a better bet. Ironically, the M3 itself is more suitable for use with older fully manual lenses via third-party adapters, without automatic aperture control.
