Canon's first-generation stabilised 70-200mm f/2.8L, adding IS to the professional telephoto.
The Canon EF 70-200mm f/2.8L IS USM launched in 2001 as the first stabilised version of Canon's professional telephoto zoom. Adding image stabilisation to the constant f/2.8 L-series formula, it became the standard professional telephoto for Canon shooters until the IS II arrived in 2010.
Optical quality is very good with sharp results across the range, though not quite matching the IS II's exceptional performance. IS provides approximately 3 stops of stabilisation — good for the era but less than the IS II's 4 stops. Ring USM is fast and silent. Build is professional L-series with weather sealing.
Canon EF mount only, 77mm filter thread. The IS II (2010) and IS III (2018) offer progressively improved IS and optics. The RF 70-200mm f/2.8L IS USM is the mirrorless version. The original IS version is the cheapest of the stabilised 70-200mm f/2.8L options.
Good value used as the IS II and III have significantly reduced prices. Check IS operation, USM motor, and overall condition. The IS provides a meaningful advantage over the non-IS version. For the price it remains a capable professional telephoto.