The Haida NanoPro Mist Black Variable Neutral Density filter offers 1.5 to 5 f-numbers with a diffusion intensity of 1/8. The filter darkens the entire image, allowing you to shoot with a wider aperture or at a slower shutter speed than is normally possible to reduce depth of field or extend shutter speeds to increase image blur. When recording video, more precise control of frame rate, exposure and depth of field can be achieved.