With 21 lens elements in total arranged in 15 groups, including four FLD elements, three SLD elements, and two aspherical elements, the lens construction optimizes the reproduction of bright points of light. It also means the lens is sharp across the entirety of its viewing angle. The two rear sheet filter slots and the included Arca-Swiss compatible tripod collar benefit the long exposures necessary for astrophotography. The lens is also designed to handle all conditions of incident light, including high backlight resistance, to consistently promote clarity, sharpness, and overall image quality. Additionally, its dust- and splash-proof body and the water- and oil-repellent lens coating mean the lens can withstand exposure to the elements.