Sigma's 'Bigma' for Canon — the 50-500mm covering everything from standard to super-telephoto.
The Sigma 50-500mm f/4-6.3 APO HSM, commonly known as the 'Bigma', is one of the most ambitious super-telephoto zooms ever produced for Canon EF-mount full-frame cameras. The 10x zoom ratio from 50mm to 500mm covers standard through extreme super-telephoto in a single lens.
The lens spans 50–500mm with a variable f/4–6.3 aperture, APO apochromatic glass for colour correction across the extreme zoom range, HSM autofocus, EX professional build, DG full-frame coverage, and a tripod collar.
The 'Bigma' nickname reflects its ambition — covering 50–500mm at professional quality is genuinely impressive, even if the f/4-6.3 aperture is modest at the long end. It competes with the Tamron 150-600mm and Nikon 200-500mm as a single-lens wildlife solution, though with the added wide-angle capability from 50mm. Previously a popular wildlife zoom before dedicated longer-range alternatives became available.
Test HSM autofocus tracking speed at 500mm. Verify APO glass condition across the zoom range. Check tripod collar rotation. Inspect zoom ring for smooth travel — a 10x zoom range is mechanically demanding. Examine front element condition.