Sigma AF 17

The Sigma 17-50mm f/2.8 delivers solid image quality. No glaring image quality issues were encountered, and the lens was definitely usable even wide-open at f/ ...

2015年4月24日 — Stellar sharpness from this lens - Sigma has really done a nice job with it. Sigma 17-50mm F2.8 EX DC OS HSM.

2011年8月3日 — With a wide open f/2.8 aperture, the Sigma 17-50mm f/2.8 EX DC OS HSM Lens is impressively sharp in the center throughout the focal length range ...

This is a very nice zoom lens! It is pretty sharp even wide open. Using it for astrophotography, stars are sharp across much of the field wide open (out to ...

Sigma 17-50mm F2.8 EX DC OS HSM test and review. With this 17-50mm F2.8 lens for Nikon, Sigma offers a very high end wide-angle zoom at a very good price.

The 17-50mm f/2.8 EX DC HSM OS features the slightly simplified version of Sigma's HSM (hypersonic AF motor). It is still fast and nearly silent but full-time ...

The build quality of the Sigma lens is pretty good although it stays a little short of the high expectations that we associate with a Sigma EX (Excellence) ...