The Sigma 12-24mm f/4 Ultra wide-angle zoom lens has a maximum aperture of F3.5 throughout the entire zoom range, making it suitable for low-light and indoor photography. Its wide-angle of view from 102.4 degrees produces striking images with exaggerated perspective, enabling photographers to emphasise the subject. ELD (Extraordinary Low Dispersion) glass, SLD (Special Low Dispersion) glass and Aspherical lenses provide excellent correction of all types of aberrations. The Super Multi-Layer lens coating reduces flare and ghosting and creates high image quality throughout the entire zoom range. The HSM (Hyper Sonic Motor) ensures fast and quiet autofocus, while allowing full-time manual focus override.