Spanning a versatile zoom range and characterized by its bright design, the Tamron 17-70mm f/2.8 Di III-A VC RXD is a 25.5-105mm-equivalent lens for APS-C-format Sony E-mount mirrorless cameras. The wide to short-tele range is ideal for everyday shooting and the fast f/2.8 constant maximum aperture suits working in difficult lighting conditions and offers improved control over depth of field. Complementing this design is a series of specialized optics, including aspherical and low dispersion elements, that produce well-corrected imagery with high sharpness, clarity, and color accuracy. Individual elements also feature Tamron's BBAR coating, which suppresses flare and ghosting for greater contrast when working in backlit and harsh lighting conditions.

Adding to the versatility of the zoom design is a Vibration Compensation image stabilization system, which reduces the appearance of camera shake for steadier photo and video recording in low-light conditions. Also benefitting handling, an RXD stepping motor enables quick, near-silent autofocus performance along with full-time manual focus override and a minimum focusing distance of 7.5". Suiting this lens's use in inclement weather conditions, it also features a moisture-resistant construction along with a fluorine-coated front element to protect against fingerprints and smudging.