1. Lenses are precise device, do not put it on strong vibration, high temperature and humidity environments.
2. Do not watch at high bright objects such as sun on your eyes in case of injured.
3. Violently operations in screw the lens on or off the camera should be prevented.
4. Do not touch the glass by your finger. In case of this happens, please clean it with soft cloth soaking with a bit of ethanol.