Mixing a useful zoom range with a sophisticated design, the Canon EF-mount Sigma 17-70mm f/2.8-4 DC Macro OS HSM is a Contemporary-series lens, also characterized by its compact, lightweight profile. The bright f/2.8-4 maximum aperture range pairs with the wide-angle to short-telephoto zoom range to create an ideal travel and everyday lens. The optical design uses a series of low dispersion and aspherical elements to control color fringing and distortion in order to realize high clarity and sharpness. A Super Multi-Layer Coating has also been applied to suppress flare and surface reflections for improved contrast in bright conditions. Also, this zoom sports a high 1:2.8 maximum magnification and 8.7" minimum focusing distance to suit working with close-up subjects.
In terms of handling, a Hyper Sonic Motor is incorporated in the design to provide fast, quiet, and precise autofocus performance along with full-time manual focus override. An Optical Stabilizer also minimizes the appearance of camera shake for sharper handheld shooting. Additionally, the 17-70mm f/2.8-4 features a rounded seven-blade diaphragm for smooth bokeh quality and it is compatible with the optional USB Dock for fine-tuning focusing characteristics and updating its firmware.
- As part of the Contemporary line within Sigma's Global Vision series, this lens is designed to achieve a balance between convenience and performance, and meshes a compact, lightweight build and versatile handling with notable optical attributes.
- Wide-angle to short-telephoto zoom is designed for APS-C-format Canon EF-mount cameras and provides a 27.2-112mm equivalent focal length range.
- Bright f/2.8-4 maximum aperture range is suitable for working in available light conditions and also benefits depth of field control for isolating subject matter.
- One Special Low Dispersion (SLD) and two F Low Dispersion (FLD) elements are featured in the optical design and help to reduce color fringing and chromatic aberrations for improved clarity and color accuracy.
- Three aspherical elements are used to help limit distortion and spherical aberrations and also contribute to greater overall sharpness and accurate rendering.
- A Super Multi-Layer Coating has been applied to lens elements in order to minimize lens flare and ghosting and contribute to producing contrast-rich and color-neutral imagery, even in backlit conditions.
- Ideal for close-up shooting, this lens offers a 1:2.8 maximum magnification along with a minimum focusing distance of 8.7" to suit working with nearby subjects.
- Integrated HSM (Hyper Sonic Motor), along with a rear focus system, realizes quick and quiet autofocus, which is further complemented by an optimized AF algorithm to produce smoother focusing performance. The HSM also permits full-time manual focus control simply by rotating the focus ring at any time.
- Optical Stabilizer system minimizes the appearance of camera shake to benefit making sharper imagery when shooting handheld.
- Rounded seven-blade diaphragm contributes to a smooth and pleasing bokeh quality.
- Constructed using a Thermally Stable Composite (TSC) material for greater precision and use in wide temperature variations. Additionally, a brass bayonet affords improved mounting accuracy and rigidity.
- This lens is compatible with the optional Sigma USB Dock for fine-tuning different lens characteristics and updating its firmware.
