The Tamron 28-75mm f/2.8 Di III RXD Lens, designed for full-frame Sony E-Mount Mirrorless Cameras, is a wide-angle zoom lens, & can also be used with APS-C models, where it will provide a 25.5-42mm equivalent focal length. Its constant, bright f/2.8 maximum aperture, is designed to provide consistency throughout the zoom range, providing improved control over your depth of field.
Both XLD (EXtra Low Dispersion) & LD (Low-Dispersion) elements are included in the optical design, to reduce color fringing & chromatic aberrations, while providing improved clarity & color accuracy in your images. A Broad-Band Anti-Reflection (BBAR) Coating has also been applied to individual elements, in order to suppress internal reflections, flare, & ghosting, while providing a greater level of contrast, & color accuracy, while working in strong lighting conditions.
The Tamron 28-75mm f/2.8 Di III RXD Lens includes an RXD (Rapid EXtra-Silent Stepping Drive) Autofocus Motor, which provides extremely quiet, fast, & smoothing focusing, for both video & stills applications. Full-time manual focus override is also available, & is compatible with Sony's "Direct Manual Focus" function, or fine-tuned manual control. A rounded nine-blade diaphragm is featured, in order to enable you to produce a pleasing bokeh quality, during the use of selective focusing techniques.
The lens features a moisture-resistant construction, & is protected against dirt, dust, & smearing by a fluorine coating.