Eye-controlled focusing: Through the tracking of eyeball movements, EOS cameras equipped with eye-controlled focusing (ECF) are able to choose the appropriate autofocus point based on where the user is looking in the viewfinder frame. ECF comes especially useful in sports photography where the subject may shift its position in the frame rapidly.
Quick control dial: Most prosumer and professional level EOS cameras feature a large quick control dial (QCD) on the camera back. Allowing easy operation of the camera using the thumb, the QCD is used for quick access to often-used functions that may otherwise require a more complicated procedure of button-presses and dial-clicks
Multi-point autofocus system: Currently, top-line EOS cameras have 61 autofocus (AF) points, the most in their class. Two Canon cameras have this system—the EOS 5D Mark III, on sale since March 2012, and the EOS-1D X, announced in October 2011 and originally scheduled for sale in April 2012, but delayed until June 2012. The release of the 5D MkIII gave Canon the lead once again in this category; previously, its top-line cameras had 45 AF points, which led the industry until Nikon released its D3 and D300 DSLRs with 51-point AF systems. A higher number of AF points increases the chances of a sharply-focused photograph in situations where the subject travels across the frame at high speeds (e.g., sports, birds). The number, type, features and performance of autofocus point array systems is likely to continue to evolve.