The NiSi 49mm HUC PRO Nano IR Neutral Density Filter ND8 (0.9) 3 Stop is specially designed to reduce the amount of light entering the camera by 3 stops. This filter is made from high-quality optical glass with nano coating to prevent losing any single bit of detail. Neutral density filters do not affect the colouration of the image and the 0.9 density provides a 3 stop reduction in light from entering the lens.