Here is a Canon RF 16mm f/2.8 STM review by one of our favorite gear…
Imaging Resource felt the pulse of the Canon EOS 5Ds R, Canon’s 50MP full-frame DSLR that competes with medium format cameras.
From the conclusion:
All said and done, despite its limited high ISO sensitivities, its limited video capabilities, and increased technical skill involved with getting sharp, properly focused images, the Canon 5DS R is an all-around impressive camera. The 5DS R is Canon’s highest-resolution EOS body to date, and it can capture some seriously impressive, incredibly detailed, ultra sharp photographs.
Its high price point and aforementioned limited features put the 5DS R squarely into a niche category. If you want a more all-around, general use full-frame Canon DSLR with a more versatile ISO range and more video capabilities, the 5D Mark III is the better bet. However, for portrait, editorial, landscape or nature photographers looking for extreme image detail in a tried-and-true Canon DSLR package — and don’t want or need the increase in bulk and expense of a digital medium format system — the Canon 5DS R will fit the bill. Read the review at Imaging Resource.