 Additionally it has a 14-bit A to D converter providing greater bit depth than previous versions.DIGIC III provides face detection AF/AE, which finds and tracks up to nine faces at once and controls exposure and flash to ensure proper illumination of the faces as well as the rest of the frame, reducing the detrimental effect of overexposed or darkened faces in a photo.It reverts to the AiAF system if the subject is either not detected or not deemed to be a subject (based on the "iSAPS" database).