Sigma has enjoyed something of a renaissance in recent years thanks largely to its premium ‘Art’ series of fast primes. This now encompasses five f/1.4 primes at focal lengths of 20mm, 24mm, 35mm, 50mm and 85mm, plus two new f/1.8 lenses in the shape of the ultra-wideangle 14mm f/1.8 DG HSM and the 135mm f/1.8 DG HSM medium telephoto prime we have here. Available for Nikon, Canon and Sigma mounts, the 135mm f/1.8 DG HSM can also be used with Sony E-mount cameras via an optional Sigma MC-11 lens-mount converter (£200).
Measuring 115mm long and 91.4mm in diameter, the 135mm f/1.8 DG HSM is by no means a small lens. Weighing 1,130g it’s not exactly light either. This makes it better suited to larger DSLRs where its size and weight can be more evenly counter-balanced. Designed primarily for full-frame DSLRs, it can also be used on APS-C cameras where it provides the 35mm equivalent of 202mm on Nikon and Sony cameras, and 216mm on Canon models.
Build quality is excellent, with the exterior finished in a mixture of metal and high quality plastic. In use, the large focus ring moves extremely smoothly, with a display window indicating the focus distance. Autofocus is driven by an ultrasonic-type hypersonic motor with full-time manual focus override. This enables the lens to lock onto subjects quickly while ensuring that the lens remains almost silent during operation.
Image quality is nothing short of stunning, with the 135mm f/1.8 DG HSM delivering pin-sharp results in the centre of the frame at all apertures. Stopping down to f/5.6 delivers equally sharp edges too. Used wide open the nine rounded aperture blades produce beautifully rounded bokeh in out-of-focus areas, while distortion and purple fringing is almost completely absent too.