The Leica E39 UV Infrared Filter is recommended for CCD applications where digital image sensors have not been fitted with an IR protection filter. Specifically the Leica M8, because of space limitations between the lens mount and the sensor Leica had to limit the amount of infrared filtering done at the sensor. Because of this you can get pinkish blacks when photographing in certain lighting conditions. This filter will eliminate this problem. This filter is completely clear and it requires no increase in exposure. Its filter factor is 1. It can also serve as a protection and filter out unwanted UV and infrared light rays.