David Arbogast wrote in post #17606465
I have been experimenting with raw files that have been variously made available and I am quite impressed. I cannot find even a trace of the pattern noise that plagued Canon sensors for far too long. Shadow recovery, while still no match for Sony's sensor, seems impressive for a Canon sensor and generally satisfactory to me. Though not as clean as a D810 raw file, at low-ISO the noise seems even aesthetically pleasing to me; a fine natural-looking grain. I am admittedly phobic about noise, but I haven't seen anything yet that offends me.
Pattern noise in the shadows is certainly one thing that made the 5D2 (and, to a lesser extent, the 5D3) less than ideal for landscapes - in the case of the 5D2, it made the usable DR closer to 7 stops than 11 stops. 12 usable stops is certainly a huge improvement, but still puts it a 2-stop GND filter away from Sony/Nikon.
As anyone who shoots landscapes knows, a two-stop GND is often the difference between a great shot and no shot at all.
Regarding wildlife photography, there are some excellent examples being posted on the FM Forum:
http://www.fredmiranda.com/forum/topic/1370747/8
The level of detail and sharpness is impressive.
Since its announcement back in February my interest in the 5DS R has fluctuated and waivered, but now that I am seeing images my interest level has peaked to its highest level. Sure, I do wish the DR was a bit better, but on the whole I feel Canon has done enough (50 MP, zero pattern noise, improved shadow recovery, etc.) to captivate my interest and strong likelihood of purchasing.
I'm interested in this camera mostly as a wildlife camera. It may not have the low-ISO DR of a landscape camera, but its performance at ISO 800-3200 is as good as any other. The combination of full-frame sensor and high pixel density essentially turns every supertele into a zoom lens, with full-frame image quality and a wider angle of view when the subject fills the frame, but with image quality equal or better than a crop-sensor camera when some cropping is needed.