>>4370447DPReview.com has a 50mp 5DsR cityscape RAW we can use for comparison. Unfortunately the foreground buildings are severely underexposed in order to test dynamic range. The foreground had to be pushed ~3ev for this comparison. Because the 5DsR uses Canon's older ADC architecture a push like this produces more noise than a modern camera would produce, which compromises resolving power. Still, it's the best we have with publicly available RAWs for this camera.
To produce this comparison the 5DsR was opened in ACR. Foreground detail was pushed ~3 stops. To try and compensate for the underexposure, sharpening and NR were used in ACR, but there's no way to restore the full resolution that would be there if the foreground had been exposed correctly. In the foreground this RAW is closer to maybe 40mp than 50mp due to the noise and the need to apply NR.
After conversion the image was scaled in a single step to the scan width of 34,513 pixels using Preserve Details 2.0. No other processing was done in PS or any other program. 2,500 pixel square crops were then taken from the 5DsR image and the CMS 20 II scan. On a 216 ppi 4k monitor the crops are equivalent to viewing a 160" print.
