10 20mm f35 ex dc hsm ultra wide angle zoom lens with a large constant aperture of f35 designed specifically for digital slr cameras this ultra wide angle zoom lens has a maximum aperture of f35 throughout the entire zoom range making it suitable for low light and indoor photography itrsquos wide angle of view from 1024 degrees produces striking images with exaggerated perspective enabling photographers to emphasise the subject eld extraordinary low dispersion glass sld special low dispersi