This page evaluates performance of the Leica 28mm f/2 Summicron-M ASPH on the 47-megaixel Panasonic S1R from f/2.8 through f/8.
In diglloyd Leica M:
Leica 28mm f/2 Summicron-M ASPH Aperture Series: Mosaic (Panasonic S1R)
Includes images up to full camera resolution from f/2.8 through f/8, including 6000 pixel width for perspective versus the Leica M10/Leica M240.
f5.6 @ 0.4 sec, ISO 100; 2019-04-09 19:35:03[low-res image for bot]
Panasonic S1R + Leica 28mm f/2 Summicron-M ASPH RAW: Enhance Details, LACA corrected