PRODUCT HIGHLIGHTS1. A telephoto zoom so compact you want to carry around everyday Tamron has adopted a dedicated design for mirrorless cameras and achieved a compact size once again by fixing the aperture at F/6.3 at the telephoto end. The maximum diameter is 77mm. Measuring just 148mm and weighing a mere545g, this 70-300mm F/4.5-6.3 Di III RXD is the world’s smallest and lightest telephoto zoom lens for full-frame mirrorless cameras. Compatible with Sony’s popular E-mount cameras, it has been developed with the concept offering  photographers to more easily experience the universe of full-scale, full-frame 300mm telephoto photography.In addition, the AF drive system incorporates the exceptionally quiet RXD (Rapid extra-silent stepping Drive) stepping motor. Because this lens is compatible with Sony camera features, including in body image stabilization and Eye AF, you can enjoy comfortable, high-speed, high precision telephoto photography, even handheld.Experience the excitement of bringing distant subjects closer as well as the perspective flattering characteristics achieved by full-scale telephoto photography more easily than ever before. For landscapes, sports, birds and wildlife as well as closer subjects such as portraits and street scenes, this lens expands the range of telephoto photography.2. Superior optical performance and supreme lightweight portability Pursuing lightweight design as a top priority, Tamron has created a compact 70-300mm F/4.5-6.3 zoom lens that makes 300mm telephoto shooting easy and fun. The superb optical design is based on a rigorous simulation processing state-of-the-art design technologies. As a result, Tamron has successfully struck a balance between extreme lightness (545g) and compactness, incorporating a slim lens barrel with a maximum diameter of 77mm without sacrificing high image quality. The optical design includes15 elements in 10 groups, with an LD (Low Dispersion) lens element precisely arranged to suppress axial chromatic and other aberrations that are likely to happen with telephoto zoom lenses. At 300mm, a commonly used telephoto zoom focal length, the design delivers excellent resolution from edge-to-edge. Overall, the efficient optical construction (which also contributes to its light weight) plus Tamron’s BBAR (Broad-Band Anti-Reflection) Coating with its well-established reputation anti-reflection properties, combine to enable the photographer to capture extremely clear, crisp images across the entire zoom range. While the lens features an advanced design with excellent core image quality, optical performance can be enhanced even further by employing the lens correction features found on Sony cameras.PRODUCT HIGHLIGHTS1. A telephoto zoom so compact you want to carry around everyday Tamron has adopted a dedicated design for mirrorless cameras and achieved a compact size once again by fixing the aperture at F/6.3 at the telephoto end. The maximum diameter is 77mm. Measuring just 148mm and weighing a mere545g, this 70-300mm F/4.5-6.3 Di III RXD is the world’s smallest and lightest telephoto zoom lens for full-frame mirrorless cameras. Compatible with Sony’s popular E-mount cameras, it has been developed with the concept offering photographers to more easily experience the universe of full-scale, full-frame 300mm telephoto photography.In addition, the AF drive system incorporates the exceptionally quiet RXD (Rapid extra-silent stepping Drive) stepping motor. Because this lens is compatible with Sony camera features, including body image stabilization and Eye AF, you can enjoy comfortable, high-speed, high precision telephoto photography, even handheld.Experience the excitement of bringing distant subjects closer as well as the perspective flattering characteristics achieved by full-scale telephoto photography more easily than ever before. For landscapes, sports, birds and wildlife as well as closer subjects such as portraits and street scenes, this lens expands the range of telephoto photography.2. Superior optical performance supreme lightweight portability Pursuing lightweight design as a top priority, Tamron has created a compact 70-300mm F/4.5-6.3 zoom lens that makes 300mm telephoto shooting easy and fun. The superb optical design is based on a rigorous simulation processes state-of-the-art design technologies. As a result, Tamron has successfully struck a balance between extreme lightness (545g) and compactness, incorporating a slim lens barrel with a maximum diameter of 77mm without sacrificing high image quality. The optical design includes15 elements in 10 groups, with an LD (Low Dispersion) lens element precisely arranged to suppress axial chromatic and other aberrations that are likely to happen with telephoto zoom lenses. At 300mm, a commonly used telephoto zoom focal length, the design delivers excellent resolution from edge-to-edge. Overall, the efficient optical construction (which also contributes to its light weight) plus Tamron’s  BBAR (Broad-Band Anti-Reflection) Coating with its well-established reputation for anti-reflection properties, combine to enable the photographer to capture extremely clear, crisp images across the entire zoom range. While the lens features an advanced design with excellent core image quality, optical performance can be enhanced even further by employing the lens correction features found on Sony cameras.With the introduction of this lens, all photographers, from first-time users of full-scale telephoto zoom lenses to experienced enthusiasts seeking a compact, lightweight telephoto zoom, can comfortably With the introduction of this lens, all photographers, from first-time users of full-scale telephoto zoom lenses to experienced enthusiasts seeking a compact, lightweight telephoto zoom, can comfortably