Fast and flexible, the camera offers superb image and video quality. The full frame sensor was designed for this model, with more autofocus points; the effective number of pixels has been increased to 22.3 million.
Most key specifications have been upgraded from the Mk II. The new sensor, along with Canon's latest DIGIC 5+ processor, gives a standard ISO range of 100?25,600, expandable to 50?102,800, allowing for better noise reduction and the ability to shoot in low light conditions. Continuous shooting at 6 fps is possible thanks to an 8-channel sensor readout. Exposure compensation is +/-5EV compared to the MkII's +/-2EV.
The shutter is rated to 150,000 cycles and incorporates the 'silent' shutter mode used on the 1D-series. Viewfinder coverage is a full 100%, and the 1040k dot, 3:2 aspect ratio 3.2-in. LCD screen offers superb anti-reflection properties and features a hardened scratch-resistant glass cover. The autofocus system has been upgraded from the MkII's nine AF points to a far more versatile 61. This is the first time Canon has installed its top-spec AF sensor into a non-series 1 camera since the days of film.
Movie formats are 1,920x1,080 pixels at 30 frames per second, 25fps or 24fps, 1,280x720 pixels at 60fps or 50fps, and 640x480 pixels, again at 60fps or 50fps, and picture quality is excellent.