The new 5DS models feature a 150K-pixel RGB+IR metering sensor that provides improved exposure metering and white-balance accuracy in a wide range of situations than the 5D Mark III’s. The 61-point AF system (with up to 41 cross-type points, 5 double-cross types and one cross type that functions at ƒ/8) is the same as the 5D III’s, but provides better focus tracking because it’s linked to the better metering system. There are also 1.3X (APS-H) and 1.6X (APS-C) crop modes, 30.5 and 19.6 megapixels, respectively, which are handy when you don’t need huge 50 MP files.
More than recent higher-end EOS DSLRs, the new 5DS models are aimed at still photographers, but they do provide video features similar to those of the EOS 5D Mark III (which remains in the EOS lineup), including 1080p at 30, 25 and 24 fps, but there’s no headphone jack or HDMI out. Continuous Movie Servo AF has been added, and you can now produce 1080/30p time-lapse movies in-camera—features likely of more use to the still photographer than the headphone jack and HDMI out.