Hoya PRO ND EX 8 reduces the amount of light passing through the lens by 3 stops. When shooting video outdoors, you can set shutter speeds to match your frame rate while maintaining the depth-of-field you want. When shooting moving objects, you can achieve a motion blur that makes the image look more cinematic. For photography applications, the filter lets you use longer exposures or achieve a shallow depth-of-field in bright sunlight.