This series from f/4 to f/11 with the Canon RF 14-35mm f/4L IS USM shows overall performance, but mainly the disappointing outer-zone sharpness that comes from the need to correct excessive distortion.
Canon RF 14-35mm f/4L Aperture Series: Big Laurel at Bend in Alpine Creek
Includes images from f/4 to f/11 up to full camera resolution, plus crops.
f5.6 @ 1/4 sec EFC shutter, ISO 100; 2021-10-28 14:34:55[low-res image for bot]
Canon EOS R5 + Canon RF 14-35mm f/4L IS USM @ 14mm
ENV: Alpine Creek, altitude 600 ft / 183 m, 65°F / 18°C
RAW: LACA corrected, distortion corrected, vignetting corrected, +20 Whites, +10 Clarity