With Canon’s Dual Pixel CMOS AF technology, every pixel on the imaging sensor is used to gather focus information, before each picture is taken. In this conceptual illustration, the actual light-sensitive photodiode area of each pixel is split into two halves, shown here as red and blue. Each separately gathers and generates focus information, before a shot is taken. Then, during actual exposure, the data from each half is combined, so for imaging purposes, the two halves act as one single pixel. Dual Pixel CMOS AF is especially important in a mirrorless-type camera, because unlike traditional DSLRs, there’s no separate AF sensor — AF detection is always done off the imaging sensor in the EOS M50.