Sigma announce new 17-70mm f2.8-4.5 lens for the Nikon AF type mount.
Or, "17-70mm F2.8-4.5 DC MACRO HSM" to provide the full name. It would probably make best sense if that were broken down into some edible bite-size chunks.
Basically you can expect a nice piece of glass that will fit onto your Nikon AF mount. Aperture range is f2.8 through to f22.
DC? - designed for digital cameras. This is because the sensors of DSLRs are significantly smaller than a 35mm SLR's film plane, therefore the physics are all different.
MACRO - that's where you can get up close and photograph in focus.
HSM - stands for 'hyper sonic motor'. Its technology that's quiet, so you don't get any nasty auto focusing noises. Plus, given that it's 'hyper' means its nice and quick! Tends to be synonymous with Nikon AF and Canon USM mounts (this lens is currently only for the Nikon mount however).
You can always expect a pretty decent bit of kit from Sigma, usually tied in with a reasonable price tag - here you'll be looking at an RRP of £290.
Also available is a 18-50mm f2.8 EX DC Macro HSM derivative - different focal length, and with particular focus to low-dispersing light glass that keeps colour abberation to absolute minimum.
www.sigma-imaging-uk.com
