This 77mm Nano-X Variable ND Filter from K&F Concept provides 1 to 9 stops of light reduction. It darkens the entire image evenly, allowing a photograph to be made with a wider aperture or slower shutter speed without overexposing your image. By slowing the exposure time or increasing the aperture, it is possible to control the depth of field and motion blur, creating a dynamic look for streams, waterfalls, landscapes, and more. Its 28-layer multicoating helps make it water- and dust-proof as well as scratch-resistant, thanks in part to its durable optical glass construction. Its putter-style ring allows you to make smooth adjustments while recording video, and its slim profile prevents vignetting when shooting with wide-angle lenses.