Canon RF 16-28mm F2.8 IS STM

Testers found the centre very sharp at f/2.8 through most of the range, with borders very good and corners good rather than excellent at 16mm, where the distortion correction stretches the image. One test also saw weaker edges around 24mm. Lateral colour fringing is very low, among the best results for an RF wide zoom, and close-focus bokeh is clean for the class. Sunstars form nicely from f/8.

Uncorrected files show severe barrel distortion, around 8% at 16mm, and black corners, so correction is mandatory and cannot be switched off in camera. Autofocus is fast and quiet, and focus breathing is low. Measured stabilisation was closer to 4 stops than the rated 5.5. The retracting barrel, plastic body, missing hood and partial sealing are the main build criticisms. One test called it a smart buy, the other questioned the price against the RF 14-35mm f/4L.

Owners praise the light weight and the f/2.8 aperture, and some pair it with the RF 28-70mm F2.8 IS STM as a compact kit that stays under 1kg. Many say sharpness is good across the zoom range and that the retracting design takes no getting used to. One chose it over the heavier RF 15-35mm f/2.8L or the slower RF 14-35mm f/4L for travel and star photography.

The complaints are the 28mm long end, corners at 16mm that never get fully sharp, the price compared with Sigma's 16-28mm on other mounts, and the lack of an included hood. One notes slightly slower focus than Nano USM lenses when racking from near to far and saw ghosting fairly easily.