The EOS-M was Canon’s first crack at making a mirrorless camera – an interchangeable lens camera (like an SLR) without a mirror. Camera review blogger Ken Rockwell described it as “the world’s first serious mirrorless camera” when it was introduced in 2012 because of its image quality. But it was widely criticised as being overpriced and having very slow autofocus, which is why Canon discontinued it. (Its replacement – the EOS M3 – is over twice the price.)
Autofocus is pretty irrelevant for serious filmmaking, and the original EOS-M can now be brought very cheaply. You should be able to find one for around $200£150 or less. This makes a good option if you want a compact camera with DLSR image quality. You can get Magic Lantern firmware to extend its video capabilities (including a 3x HD crop mode, which will triple the effective focal length of any lens you attach to it.)
With an EF to EF-M adapter (£90 from Canon, imitations available for as little as £20) you can fit any current Canon lens, and you can also buy £20-£30 adaptors to fit other makers’ prime lenses. Canon also make their own, tiny 22mm f2 ‘pancake’ medium wide angle lens for the M series, and there are also 11-22 ultrawide, 55-200 telephoto, and 15-45 ‘standard zoom’ options.
The build quality is solid. The EOS-M appears to have exactly the same sensor as the Canon 60D DSLR, but it’s a fraction of the size and weight. Much easier to carry anywhere, and useful to get a second camera angle. It’s really useful as an unobtrusive but high-quality camera, so I can record people working without poking a big SLR in their faces. The stabilised 18-55 zoom is good and the 22mm f2 lens is excellent. The touchscreen-based controls are slow to use though, so it’s good to see that the new M3 (see below) has more physical controls on the camera body.
Update: There are several current cameras in the EOS M system.
The premium EOS M5 has a built-in electronic viewfinder, fast dual pixel video autofocus, 1080p60 slow motion, and five-axis image stabilisation.
The EOS M6 has a similar specification to the M5 but without the viewfinder, though you can add one. The older EOS M3 is similar but doesn’t have 1080p 60 slow motion.EOS-M on Amazon