Sigma 17-50mm f/2.8 EX DC OS HS M £330/$370

It packs a punch at a penny-pinch­ing price

NPhoto - - Gear Zone -

Both of the Sigma DX-for­mat lenses on test have ul­tra­sonic mo­tor-based aut­o­fo­cus sys­tems. While not as fast as most ring-type ul­tra­sonic sys­tems, and while lack­ing in full-time man­ual over­ride, the rel­a­tively small mo­tor does en­able a com­pact build. Even so, this is the chunkier of the two Sigma lenses and, at 565g, is 100g heav­ier than the 17-70mm.

It beats the other Sigma DX lens in terms of hav­ing a con­stant-aper­ture f/2.8 rat­ing, but falls shorter in max­i­mum tele­photo reach. It’s also an older de­sign with an ‘EX’ des­ig­na­tion, de­not­ing ‘pro­fes­sional grade’ build qual­ity, al­though the stan­dard of con­struc­tion doesn’t feel any more ro­bust than that of the newer 17-70mm lens, and nei­ther have any weather-seals.

Per­for­mance

Helped by two FLD (Flu­o­rite­grade Low Dis­per­sion) el­e­ments, con­trast and cen­tre-sharp­ness are good through­out the zoom range. At wide aper­tures how­ever, edge and cor­ner sharp­ness are dis­ap­point­ing. Aut­o­fo­cus speed is no match for that of the Nikon DX lens.

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.