Canon's affordable RF-mount nifty fifty, bringing fast prime optics to mirrorless.
The Canon RF 50mm f/1.8 STM was released in 2020 as the most affordable prime lens for Canon's RF mirrorless system. It serves the same role as the beloved EF 50mm f/1.8 STM — an accessible fast prime for beginners and a lightweight option for experienced shooters. It covers a standard 50mm field of view on full-frame RF bodies.
Optical quality is a step up from the EF version with improved sharpness wide open and better controlled chromatic aberration. The STM motor provides smooth quiet autofocus. At f/1.8 bokeh is pleasant with seven rounded aperture blades. Build is plastic but includes a control ring which is a useful RF-mount feature. The lens is compact and lightweight.
Canon RF mount only, 43mm filter thread. This is distinct from the EF 50mm f/1.8 STM which requires an adapter on RF bodies. The RF 50mm f/1.4L USM and RF 50mm f/1.2L USM offer wider apertures at dramatically higher prices. There are no third-party RF 50mm alternatives due to Canon's mount licensing restrictions.
Commonly available used at reasonable prices. Check the control ring rotates smoothly, AF motor responds, and aperture blades operate cleanly. The small 43mm filter thread means most existing filters will not fit. Excellent value as a first RF prime lens.