Large aperture standard zoom lens designed Specially For Digital SLR Cameras.
This lens can be used with wide variety of subjects and it is an ideal large aperture standard zoom lens for digital SLR cameras featuring APS-C size image sensor. This lens has a minimum focusing distance of 20cm (7.9″) throughout the entire zoom range and has a maximum magnification of 1:2.3. The multi layer lens coating reduces flare and ghosting, which is a common problem with digital cameras.
Minimum focusing distance of 20cm (7.9″) and maximum magnification of 1:2.3
This lens has a minimum focusing distance of 20cm (7.9″) throughout the entire zoom range. Maximum magnification of 1:2.3 enables close-up photography like a macro lens. It has a 3cm (1.2″) working distance between the lens and subject and it is very convenient for taking close-up pictures.
Reduced Ghosting and Flare
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 through the entire zoom range.
Aspherical lens elements & SLD lens
A Special Low Dispersion (SLD) lens and two aspherical lens elements provide excellent correction for all types of aberrations and produce a high level of optical performance throughout the entire zoom range.
F2.8mm (at 17mm focal length)
This lens offers a large aperture of F2.8 at 17mm wide angle and performs superbly even in relatively low light conditions indoors or at dusk.
Inner focusing system
Because the front of the lens does not rotate, circular polarizing filters and a petal-type hood can easily be used. An inner focusing system eliminates front lens rotation, making the lens particularly suitable for using the petal-type lens hood supplied and also circular polarizing filters.
A magnification scale is displayed on the lens barrel, ensuring ease of use.
Zoom lock switch mechanism
A zoom lock switch mechanism is provided to prevent the lens from creeping due to its own weight, and to avoid the danger of the lens receiving a shock while it is being carried.
HSM (Hyper Sonic Motor) for Nikon Mounts Only
The Incorporation of HSM is capable of autofocusing with all Nikon DSLR cameras.
In it’s price bracket, this lens can be considered good. It’s one drawback is the distortion at the wide end, but this is one of the easier problems to cure in digital software and being designed purely for digital cameras with cropped sensors will have no effect on film users. The DC/DG coating that Sigma now uses has gone a long way to improving their lens’s contrast and this shows well in this example. The close focus ability of this offering also helps to greatly increase its versatility.
In summary, the positive points of the Sigma 17-70mm f/2.8-4.5 DC Macro are:
- Excellent close focus ability
- Good build with no wobbles
- Good resolution figures overall
The negative points are:
- Barrel distortion at the wide end
- AF not as quiet as HSM lenses