Canon's nifty fifty, the lens every EF-mount owner should have.
The Canon EF 50mm f/1.8 STM released in 2015 is the third iteration of Canon's most popular prime lens. Known affectionately as the nifty fifty, it replaced the much-maligned EF 50mm f/1.8 II. With a metal mount, STM motor, and improved optical coatings, it addressed every criticism of its predecessor while remaining extraordinarily affordable.
Sharpness is very good from f/2.8 onwards and surprisingly usable wide open at f/1.8. Bokeh is smooth with seven rounded aperture blades versus the II's five straight blades. The STM motor provides quiet autofocus suitable for video. Build is a significant upgrade from the II with a metal mount replacing the notorious plastic one.
Canon EF mount only, 49mm filter thread. Works on all EOS DSLRs and on EOS R mirrorless bodies via the EF-RF adapter. The predecessor EF 50mm f/1.8 II is still widely available used but the STM version is worth the small premium. The EF 50mm f/1.4 USM and EF 50mm f/1.2L offer wider apertures at significantly higher prices.
Extremely common and affordable used. Check the AF motor responds and the aperture blades open and close cleanly. Inspect the mount for wear. At this price there is no reason not to own one. It is the best value lens in the Canon ecosystem and a superb introduction to prime lens photography.