The Canon 5DS and 5DS R (pictured here) boast a 50.6-megapixel CMOS sensor. That's not a typo, it actually has an output resolution of 50.6 megapixels. The sensor is full-frame, just like the earlier 5D cameras. Rather than replacing the 5D Mark III, it will sit above it in the Canon range.
The two models are identical apart from one important feature: the 5DS R has a low-pass cancellation filter inside to deliver the maximum resolution from the sensor. The 5DS R is designed for photographers who need the sharpest image possible, such as landscape photographers.
The autofocus system in the 5DS and 5DS R is lifted from the 5D Mark III. This means a 61-point AF array with 41 cross-type points.
Although it looks remarkably similar to the 5D Mark III in most respects, the mode dial now features raised markings rather than a flat plate. The top LCD screen remains the same.
Befitting a professional-grade dSLR, the 5DS and 5DS R have dual card slots: Compact Flash and SD.
Sometimes, 50 megapixels is just too much. The cameras allow you to choose a crop ratio that reduces the output to 19 megapixels which is a bit more manageable for certain applications. Select from full (no crop); 1.3x (APS-H equivalent crop); or 1.6x (APS-C equivalent crop). The viewfinder also blacks out around the crop area to show you exactly what is being captured.
Let's just take a look at that image quality screen. Yep, it's definitely saying 50 megapixels…
Serious video users will still want to grab the 5D Mark III, as the 5DS and 5DS R don't have headphone monitoring. USB 3.0 is a nice addition, though.