We've waited a long time for the EOS M. A compact with an interchangeable lens was the only obvious gap in Canon's line-up, and this camera was grist for the rumour mill for just about as long as every new iPad. For a while it even looked like Canon might sit out this particular innovation in fear that it could damage its compact and dSLR brands. Fortunately it didn't, and what it's come up with immediately feels like one of the best-constructed, sturdiest compact interchangeable lens cameras out there. You can pick one up for around £550 online.
The question is, is image quality and usability equally robust. In short, was it worth the wait? There's only one way to find out...
Build and design
Canon has capped the resolution at 18 megapixels spread across an APS-C-sized sensor. If that sounds familiar it's because that's the same sensor size and resolution as you'll find in its consumer dSLR lineup. The(£415) and (£540) match it point-for-point, which might make you wonder why you'd want to buy a digital SLR at all when you can get effectively the same internals here in a far smaller body.
It largely comes down to versatility. The most obvious difference between the two is that the missing mirror inside the EOS M means it's unable to bounce the incoming light to an optical viewfinder, and so as with most mirrorless interchangeable cameras all of the composition is done using the rear LCD. Those that do sport a viewfinder have no choice but to use a digital version or, as in the case of the rangefinder-like(£1,100), offset it from the lens.
There's no built-in flash, either. Canon has bundled one in the box and it comes in a neat carry bag, but clipping this onto the hot shoe isn't nearly so convenient as flipping up a built-in lamp, and as it's powered by two AAA batteries it isn't so compact, either.
Finally there's the issue of lenses. The EOS M is bundled with an 18-55mm lens which delivers approximately 3x zoom equivalent to 28.8-88mm in a conventional 35mm camera on account of the sensor's 1.6x focal length multiplier.
This is an excellent set of metrics to get you started, but at the moment this very attractive metal-bodied lens comprises half of the entire EF-M mount line-up. Its only companion is a 22mm prime at f/2. If you want to move beyond these, or recycle your existing EF or EF-S lenses, you'll need to buy an adapter.
It's early days, though, and any new platform can be expected to grow over time if it proves to be a success. Samsung, Nikon, Panasonic and all those who have led the charge in this field have been growing their ranges of lenses and accessories over time and there's no reason to suspect that Canon won't do the same.
There are plenty of reasons, however, to sidestep to traditional dSLR and opt instead for the EOS M. It's considerably smaller, extremely well built and has all the controls you'd expect of a high-end camera in a compact body.
The 3-inch LCD is touch sensitive, and the controls are easy to navigate. A dedicated quick menu spread up and down each side lets you set white balance, picture style, image quality, focus mode and so on without trawling the full menus.
You can drag the exposure compensation through three stops in either direction by sliding your finger across the screen, and do the same with aperture and shutter speed, all of which is far faster than using the rear mounted wheel. All settings choices can be previewed in real time, so even though you wouldn't see the effect of a longer exposure until you played back the image, the relative level of captured light is simulated while you're framing your shot. You can tap to focus and, optionally, tap to fire the shutter, too.
Although it's easy to specify what you want to use as your focus point by tapping on the screen it can sometimes be slow to get a fix, even in good light, and it's disappointing that there's no switch on the side of the lens to change from auto to manual focus; instead you need to do it through the menu so it's not as easy to switch between this and autofocus as it is on a dSLR.
It's also a little disappointing that it doesn't automatically enlarge the selected focal point while you're manually turning the end of the barrel so that you can get a better fix on the effect you're having. You can, however, switch between 1, 5, and 10x magnification using a button on the screen. Other than that, though, manual focus is easy and comfortable, courtesy of a far better focusing ring than you'd find on many entry-level lenses.
When using a sufficiently narrow aperture or shooting a subject face on, the image remains sharp right into the corners, with barely any fall-off when compared directly to the centre of the shot.
At the opposite end of the scale, the maximum wide aperture also allows for some very satisfyingly shallow depths of field, should you choose, so you can isolate specific elements within the frame with ease. It's easy to pick the exact part of the frame you want to keep in focus by tapping on the LCD.
Sensitivity kicks off at ISO 100 and runs through to ISO 12,800, although in auto mode it's capped at ISO 6,400. If you need to push it to extremes you can extend it to ISO 25,600 equivalent.
I performed the majority of my tests with the camera set to aperture priority mode so that I could control depth of field while the camera compensated with automatic sensitivity, shutter speed and so on. On the first of two days of testing I was shooting under overcast skies so manually selected the appropriate white balance.
Despite this, some architectural shots were biased towards the shadows, with the histogram showing a sparseness of tones in the brightest quarter, even when the EOS M had increased its sensitivity to ISO 400. Fortunately this wasn't too serious a problem, as by shooting in raw I could rebalance the shots in post production if I so desired. This may have been caused by the EOS M selecting high shutter speeds for shots that included a generous amount of sky, with 1/1000 and 1/2000 second not unusual. Images framed to exclude the sky were perfectly balanced -- as were those shot in more favourable lighting.