Sigma APO 300-800mm f/5.6 EX DG HSM £5500, $8000

A real super-sized lens, the mighty Sigma 300-800mm gives you maximum reach

The Sigma 120-300mm and Nikon 200-400mm, which weigh about 3.4kg each and measure 366mm and 291mm respectively, are two of the heaviest and biggest lenses in this test group, but this lens dwarfs them both. The somewhat bonkers build is more than half a metre long (544mm) and the lens doesn’t so much ‘tip’ as ‘slam’ the scales at nearly 6kg. Handheld photography is off the menu, especially considering the lack an optical stabiliser, which would have been useful when shooting with a monopod.

Thanks to its constant-aperture design, the lens doesn’t extend at longer zoom settings. Features and build quality feel a bit downmarket compared with a couple of the other Sigma lenses on test. There are no weather seals, nor a focus limiter switch. That said, the minimum focus distance is a fairly long-range six metres anyway, so a focus limiter would be rather superfluous. Drop-in 46mm filters can be fitted at the rear.

Performance

Not a standout performer, sharpness is average in the 300-700mm section of the zoom range, but drops off noticeably at 800mm, even at its f/8 sweet spot. Autofocus is a little slower than with other lenses on test.