Versatile Telephoto Zoom. With a focal length equivalent to 105-315mm after crop-factor, the Pentax 70-210mm f/4 HD FA ED SDM WR is an exceptional choice for sports photography, action photography, and portraiture. Its constant f/4 aperture is consistently bright throughout the zoom range and gives you great depth-of-field control for selective focusing, but is probably a bit too slow for low-light shooting.

High-Quality Optics. The twenty-element/fourteen-group optical design features three low-dispersion elements and two anomalous-dispersion elements to help minimize chromatic aberrations while maximizing clarity and sharpness. The rounded, nine-blade diaphragm provides smooth background blurring with circular out-of-focus highlights. Pentax’s HD coatings reduce reflections and lens flare, and Super Protect coatings on the front and rear elements repel dust, water, and oils.

Supersonic Direct-Drive Autofocus and Quick-Shift Focus. The direct-drive motor offers fast, nearly silent autofocus performance with an internal-focusing design. The Quick-Shift Focus System gives you full-time manual focusing for quick adjustment, and a focus-range limiter improves focus performance when strictly shooting subjects at a great distance.

Durable Build. The 70-210’s moisture-resistant construction means it’s able to hold up in less-than-ideal shooting conditions. Pentax’s HD coatings reduce reflections and lens flare, while Super Protect coatings on the front and rear elements repel dust, water, and oils. It’s 6.9 inches long and slightly under 2.0 lbs., making it relatively compact and light for a lens with its range. On top of that, its internal zooming mechanism means that its overall length doesn’t change during use.