Sigma's professional constant f/2.8 super-telephoto zoom — the 120-300mm for sports and wildlife.
The Sigma 120-300mm f/2.8 DG OS HSM is a professional super-telephoto zoom maintaining a constant f/2.8 aperture throughout its range — an extraordinary specification that no other manufacturer offers. Released around 2012, later updated to the Sports line, it targets sports and wildlife photographers who need f/2.8 speed with zoom flexibility beyond 200mm.
Optical performance is very good. Sharpness is impressive throughout the range at f/2.8, with the APO elements controlling chromatic aberration well. OS stabilisation provides approximately 4 stops of correction. With the Sigma 2x teleconverter, it becomes a 240-600mm f/5.6 — an incredibly versatile combination. HSM autofocus is fast with customisable focus limiters.
Canon EF mount in this listing — also available in Nikon F. Filter thread is 105mm — very large and expensive. Weight is approximately 3,390 grams — extremely heavy, requiring a tripod or monopod for any sustained use. Build quality is professional with full weather sealing. A tripod collar and case are included.
Available on the used market at significantly below new prices. Check OS motor, AF accuracy, and all elements carefully. The weight is a serious practical limitation — this is not a handheld lens. The constant f/2.8 at 300mm with teleconverter compatibility makes it uniquely versatile for professional sports coverage where zoom flexibility and speed are both essential.