This Variable Fader ND2-ND400nFilter from K&F Concept is a 52mm variable neutral density filter providingnan adjustable light reduction of 1 to 8.6 stops. It darkens the entire imagenevenly, allowing a photograph to be made with a wider aperture or slower shutternspeed than normally required. By slowing the exposure time or increasing thenaperture, it is possible to control the depth of field and blur movementneasily, creating a dynamic look for streams, waterfalls, landscapes, and more.