Tamron has just announced a unique lens for Sony APS-C cameras: the 17-70mm f/2.8 Di III-A VC RXD.
Recently, Tamron has been focusing on its full frame lenses for Sony cameras and this new 17-70mm f/2.8 lens will be its first for E-mount APS-C in nine years. The lens offers a full frame equivalent of 25.5-105mm, making it a flexible all-rounder with a fast, consistent aperture — something of a rarity when it comes to lenses for crop-sensor cameras.
The RXD stepping motor — Rapid eXtra silent Drive — is the same as that found in the hugely popular Tamron 28-75mm f/2.8 lens (currently $799, down from $879) for full frame Sony cameras which suggests that it will offer excellent autofocus performance for both photos and video.
Tamron typically compromises by not offering lens stabilization but the 17-70mm features Vibration Compensation (VC) which, the manufacturer explains, uses AI when shooting video. This video from Tamron offers more details:
The minimum focusing distance is just 7.5 inches (19 cm) at its widest and 15.4 inches (39 cm) at its longest, giving it a maximum magnification ratio of 1:4.8 and 1:5.2 respectively.
The lens has a 67 mm filter thread, is 2.94 inches (74.6 mm) in diameter, is 4.7 inches (119.cm) in length, and weighs 18.5 oz (525 g). It features 16 elements in 12 groups and has 9 circular aperture blades.
The lens will be available to purchase from January 14, 2021 for $799. You can find more information on the Tamron product page.