Sigma 28-70mm f/2.8-4 DG
(From Sigma lens literature) This standard zoom lens has a large aperture of f/2.8 at 28mm focal length and yet it is compact and lightweight, with an overall length of 62.5mm (2.5) and weight of 255g (9 oz). This digitally optimized diagonal fisheye lens is equipped with a new multi-layer coating technology that reduces both flare and ghosting. This compact, large aperture zoom lens is ideal for digital and 35mm SLR cameras.
The new multi layer lens coating and lens design reduce flare and ghost, which is a common problem with digital cameras and also creates an optimum color balance.
From 28mm wide to 105mm tele range this zoom lens has 50cm (19.7 inches) minimum focusing distance. It has also maximum magnification of 1:6.5.
An aspherical lens element is used for excellent correction of distortion.
A zoom hood is supplied with this lens for complete depth in the telephoto range and glare-free shooting in the wide-angle range.
Sigma 28-70mm f/2.8-4 DG User Reviews
7 out of 10 points and recommended by martiniko (1 reviews)cheap, small and light, fast focusing, nice bokeh, accurate color; no CA!soft at widest apertures
nice walk-around lens because it focuses fast and the 28-70mm range is perfect for street photography - whioh is my style. Build is good and the rubber finish is way cool!reviewed March 22nd, 2006 (purchased for $80)
the 70mm is very soft wide open. at f6.3 sharpest center and halfway to the corners, at f8 sharp all over. I use 70mm f4 - f5.6 for close-up portraits. the softness makes portraits appealing and light.
At f2.8- 28mm, it is also soft but not as soft as 70mm at f4. Good for indoor nightshots.
if you don't look at your pictures 100% on screen this is acceptable. For best results f4.5 - f6.3 will give you center sharpness.
For its price, this is a good supplement for your kit, I don't like my Kit's 18-55mm , though sharper, it's barrel distortion annoys me and the 55mm is too short.
This lens is always on my D50.