Shoot extreme close-ups, mid-distance action shots, and portraits without the bulk of longer lenses. This jack-of-all-trades for the on-the-go photographer provides the highest level of optical quality. It is ideal for the photographer who wants a quality standard zoom lens with extra telephoto performance and a silent SDM autofocus motor.

* Zoom
* Portraits, landscapes, family, general use

• The smc PENTAX DA 17-70mm features extra zoom for a wide range of shooting applications from wide angle to telephoto.
• Bringing together advanced optical technologies, including aspherical elements, this lens is superior in contrast, clarity and edge-to-edge sharpness.
• The SDM system incorporated into this lens results in a smoother, quieter autofocusing operation using a built-in supersonic motor.*
• The PENTAX-original SP (Super Protect) coating repels dust, water and grease to keep your lens clean and your image quality at its peak.
• The PENTAX-original Quick-Shift Focus System allows instant switching from autofocus to manual focus operation.
• The focal length is equivalent to 26-107mm in the 35mm format.
• Developed specifically for PENTAX digital SLR cameras.

*SDM-only focusing lens can still be used with non-SDM PENTAX DSLR bodies in manual focus mode.

Read more at Pentax

Reviews

Pentax smc DA 17-70 mm f/4.0 AL [IF] SDM review by lenstip.com

Pros:

• universal focal lengts range and decent fastness,
• solid body,
• very good frame centre picture quality,
• good frame corner quality at 17 mm and more,
• good chromatic aberration correction,
• the lowest vignetting in its class,
• high transmission and good colour reproduction,
• quick, silent and efficient autofocus system.

Cons:

• the manual focus ring moves too easy and is too small,
• weak against the bright light performance,
• too little frame corner resolution at 17 mm.

Pentax SMC DA 17-70mm f/4 AL [IF] SDM – Review / Test Report by photozone.de

The Pentax DA SMC 17-70mm f/4 AL [IF] SDM is undoubtedly the most desirable standard zoom lens in the current Pentax lens lineup. The resolution characteristic is very good without any significant weakness. The vignetting and distortion are about average for a lens in this class. The lateral CAs are relatively well-controlled although you may spot some traces in field conditions when using wide-angle settings. The quality of the bokeh (out-of-focus blur) seems to be very fine albeit limited compared to fast prime lenses naturally. Contra-light situations are handled fairly well with comparatively underdeveloped ghosting problems. Typical for most Pentax DA lenses the build quality is on a very high level. The fast and near-silent ultrasonic AF is also a very welcome new feature. All-in-all a very harmonious package selling for a very fair price of around 480€/US$.

Links

smc PENTAX-DA 17-70mm F4 AL[IF] SDM Press Release (DPReview.com)