This 72mm MRC Nano Master #810 ND Filter from B+W is a precision-crafted neutral density filter that reduces an exposure by 10 stops for finer control over exposure settings. By increasing the density evenly across the entire image area, the depth of field can be reduced to help isolate the image subject, even in brightly lit conditions. In addition, the shutter speed can be reduced to increase image blur and enhance the sense of movement, or smooth out the look of rushing water.