a professional-grade, ultra-wide-angle zoom lens designed for Full-Frame DSLRs, featuring a fast, constant f/2.8 aperture, exceptional edge-to-edge sharpness, and robust dust/water-resistant construction.

• Optics: Features 16 elements in 12 groups, with special coatings designed for digital cameras to minimize flare and ghosting.
• Autofocus: Equipped with a ring-type Ultrasonic Motor (USM), internal focusing system, and fast CPU, offering quick, near-silent autofocus with full-time manual override.
• Design: Robust L-series build with dust and water resistance, featuring an 82mm filter thread.
• Image Quality: Optimized for superior resolution, contrast, and color fidelity, particularly in wide-angle, low-light, or landscape/architecture photography.
• Bokeh: The nearly circular aperture provides smooth, natural background blur.