Precise Metal Structure: The sturdy and durable all metal lens body structure ensures the assembly accuracy and durability of the lens; the brass metal mount fits closely to the body and is more durable. Extremely Fast and Accurate Autofocus: The combination of internal focus and STM and screw type stepping motor is used to achieve fast, accurate and quiet autofocus through the optimization and adaptation of the camera's autofocus algorithm, and to track the subject quickly and sensitively. Take control of dynamic photo and video capture with ease. 13mm F1.4 Lens: F1.4 large aperture soft focus, 13mm ultra wide angle visual impact, electronic aperture, internal focus, the lens length remains unchanged. Outstanding High Resolution Performance: 11 groups of 14 optical structure design, 2 aspherical lenses, optimized distortion performance and off‑axis optical aberration, so that the lens maintains high definition performance throughout the entire imaging range. Holographic Field Low Dispersion: 4 ED (low dispersion) lenses can effectively improve magnification chromatic aberration, reduce radial glare, accurately display point light sources, and ensure excellent contrast and accurate color reproduction at various aperture values.