This filter is made of high-quality optical glass with a nano-coating to prevent loss of detail. Neutral density filters do not affect the color of the image, and a density of 3.0 results in a reduction of light entering the lens by 10 stops. When you attach a neutral density filter (ND) to your lens, the amount of light entering the lens is evenly reduced. The ND filter is helpful when the contrast between highlights and shadows is too great to achieve a good exposure. The ND filter can also allow for greater motion blur and image details by using a wide aperture and/or a long shutter speed.