Tamron's landmark affordable f/2.8 zoom for Sony mirrorless that disrupted the market.
The Tamron 28-75mm f/2.8 Di III RXD launched in 2018 and disrupted the Sony FE lens market by delivering a constant f/2.8 standard zoom at roughly one-third the price of the Sony 24-70mm f/2.8 GM. It proved that third-party mirrorless lenses could be excellent, compact, and affordable.
Optical quality is very good with sharp results across the frame, particularly impressive for the price. The constant f/2.8 provides professional-class depth of field control. RXD autofocus is fast and near-silent. Build is weather sealed and compact at just 550g.
Sony FE mount, 67mm filter thread. The 28mm starting point is narrower than the GM's 24mm. The Tamron 28-75mm f/2.8 G2 succeeded it with improved optics. The Sigma 24-70mm f/2.8 DG DN Art offers a wider range at a higher price.
Excellent value used. Check RXD AF speed, zoom ring, and weather seals. This lens was the reason many photographers chose the Sony system. The G2 is sharper but the original remains outstanding value.