It's the effect of todays' turbo capitalism. In any case, whatever camera you choose, you will have great image quality. I bought the EOS R one month ago and I'm extremely happy with it, it produces outstanding images. Keep in mind that the EOS R has the same sensor as the 5D Mark IV, but for a fraction of the price. Canon 5D Mark III vs. Fuji X100S image quality 09 January 2014. Canon 5D Mk III vs. LEICA M 240 vs. Sony A7 Image Quality Comparison 19 December 2013. Canon 6D. Similar image quality smaller, lighter package with a few less controls, but with added Wi-Fi and GPS. Canon 5D Mark III versus Canon 6D. Unfortunately, the 6D Mark II has a worse dynamic range than the Mark I. The Canon 6D Mark II has worst dynamic range than the previous 6D and only matches the 2008 Canon 5D Mark II. Credit mubJdu.

canon 6d mark ii vs 5d mark iv image quality