This was the Canon 24mm Tilt-Shift, Lii, on a Sony A7r via Metabones compared to the OEM Sony/Zeiss ("Zony") 35mm. Cylindrical stitching was done in PS without first expanding the files (which would have make the stitched image better). The straight 24mm was up-res'd with bicubic to match 35mm stitch pixel density.
(The 24-105 zoom at the edge is not close to as good as the 24 TS.)
This is, in part, where demand for larger prints may be coming from.
FWIW
Paul