Canon EOS - M

It's now almost four years since Panasonic first introduced us to the mirrorless interchangeable lens camera, in the shape of the Micro Four Thirds Lumix DMC-G1. Since then, all of the other major manufacturers have entered the fray, in the process offering cameras in a variety of shapes and sizes - from diminutive beginner-friendly models such as the Olympus PEN E-PM1, to unashamedly high-end models like the Sony NEX-7 and Fujifilm X-Pro1. Nikon, meanwhile, has ploughed its own individual furrow with its family-friendly 1 J1 and 1 V1 models. This simply reflects the fact that different cameras are targeted to different kinds of users - be they serious enthusiasts looking for a small, highly capable camera, or compact-camera upgraders looking for SLR-like image quality in a smaller, easier-to-use package.

Canon is the last big player to show its hand, and its initial entrant - the EOS M - is unashamedly targeted to the latter group of users. To all intents and purposes it's a mirrorless version of the recently-announced EOS 650D, but with a simpler interface that's designed to be more approachable for novice users, and obviously much more compact in size. It's based around a new 'EF-M' lens mount, and two matched lenses will be available at launch: the EF-M 18-55mm f/3.5-5.6 IS STM zoom, and the EF-M 22mm f/2 STM 'pancake' prime. But it's still very much part of the EOS system, and all of the company's existing EF and EF-S SLR lenses can be used via the co-announced 'Mount adapter EF-EOS M'.

The EOS M features a compact, magnesium-alloy body, and will be available in four colours - black, white, silver and red. It has no built-in flash, but instead a hot shoe on the top plate, and in many markets (although not the US) it will come bundled with the new AAA-powered Speedlite 90EX unit. There's neither a built-in viewfinder, nor connector for an external unit - composition is solely using the camera's rear screen (which is fixed, rather than articulated).

Canon EOS M key features

• New EF-M lens mount (optimized for APS-C sensor size)
• 18MP APS-C 'Hybrid CMOS' sensor
• Continuous autofocus in movie mode with subject tracking
• 14-bit DIGIC5 processor
• ISO 100-12800 standard, 25600 expanded
• 4.3 fps continuous shooting, 3 fps with autofocus tracking
• 1080p30 video recording, stereo sound (with 25p or 24p options)
• External microphone socket and adjustable sound recording level
• 1040k dot 3:2 touch-sensitive ClearView II LCD (capacitative type, multi-touch support)
• Standard EOS hot-shoe for external flash (no built-in flash)
• 'Creative Filters' image-processing controls, previewed live on-screen

New EF-M lens mount
A new mirrorless system needs a new lens mount, which Canon has called EF-M to emphasis its continued compatibility with the company's existing EF mount for autofocus SLRs. It's a fully-electronic bayonet mount, with 9 contacts between the lens and camera. Unusually, the white dot for aligning the lens is at the 11 0'clock position on the mount.

The EF-M mount is 58mm in diameter, with a flange distance of 18mm from the bayonet to the sensor. As the image above clearly shows it's matched specifically to the APS-C sensor size. So don't expect a future full frame EF-M mount camera - it's not going to happen.

Like all other mirrorless cameras, the EOS M's shutter is open by default even when the camera is turned off, exposing the sensor. This may seem disconcerting to SLR owners, but we've never experienced any problem with this approach. Like Canon's live view-capable SLRs the EOS M uses an electronic first curtain to activate the exposure, and the physical shutter is only used to end it. This helps reduces shutter lag and keep shutter noise down - meaning the EOS M is one of the quieter models of its type.

source: dpreview, more detail info, visit dpreview.