Canon's classic L-series telephoto — the EF 300mm f/4L IS with professional optics and stabilisation.
The Canon EF 300mm f/4L IS USM was released in 1997 as Canon's professional 300mm telephoto with the convenience of f/4 and IS stabilisation in a more portable package than the f/2.8L. The L designation provides fluorite and UD elements. IS provides approximately 2 stops of stabilisation. A favourite of wildlife and sports photographers who value portability.
Optical performance is excellent — genuine L-series quality. Sharpness is outstanding from f/4. The fluorite element controls chromatic aberration superbly. IS stabilisation enables handheld telephoto work that would be impossible without. Ring-type USM provides fast, quiet AF. Compatible with Canon 1.4x and 2x extenders for 420mm and 600mm reach.
Canon EF mount, full-frame. Filter thread is 77mm. Weight is approximately 1,190 grams — significantly lighter than the 300mm f/2.8L. Build quality is outstanding L-series with full weather sealing. The tripod collar is removable for handheld use. The relative portability versus the f/2.8L makes this practical for handheld wildlife and hiking.
Available at very attractive used prices — the Canon RF 100-500mm has reduced demand. Check IS motor and AF accuracy. One of Canon's best-value L lenses. The combination of L-series optics, IS, and relatively portable size creates an outstanding handheld super-telephoto. Adapts to RF mount via EF-RF adapter with full functionality.