[. . . ] For your safety on use of a lens Before operating, pay special attention to the following remarks. [. . . ] If the lens emits smoke, smells of smoke or gives off heat, discontinue use immediately. Do not install the lens in a place where vibration and shock are expected. Do not use organic solvents, such as thinners, alcohol or benzine to remove stains from the lens. When grease or fingerprints are on the lens, wipe them off with a lens cleaning paper and lens cleaner gently forming a swirl from the center to the circumference. [. . . ] When removing the lens, keep turning the lens counter-clockwise until the lens comes off. [. . . ]