Sigma's earlier 120-300mm f/2.8 — the first generation constant-aperture super-telephoto zoom.
The Sigma 120-300mm f/2.8 EX APO DG HSM is the earlier generation of Sigma's extraordinary constant f/2.8 super-telephoto zoom described in the OS version under ID 3514. The constant f/2.8 at 300mm is a specification no other manufacturer offers in a zoom. This version lacks OS stabilisation — addressed in the later version.
Optical performance is good. The constant f/2.8 throughout 120-300mm is the unique specification. APO elements with SLD glass control chromatic aberration. HSM motor provides fast, quiet AF. Compatible with Sigma 1.4x and 2x teleconverters for 420mm f/4 and 600mm f/5.6 combinations. The zoom flexibility with f/2.8 speed is unmatched.
Nikon F mount. Filter thread is 105mm — very large. Weight is approximately 3,190 grams — extremely heavy. Build quality is professional grade. No OS — the main limitation. Tripod collar included and essential. A tripod or monopod is absolutely required for any sustained use at this weight.
Available at lower prices than the OS version. Check AF and smooth zoom. The non-OS version is cheaper but the lack of stabilisation at 300mm is a significant practical limitation. The OS version is strongly preferred. Best for tripod-based sports and wildlife where the constant f/2.8 zoom flexibility is valued.