"The Bower 67mm Variable Neutral Density Filter is designed for analog and DSLRs; this specialty filter give you the ability to use fast film or low aperture in bright outdoor conditions. ND or neutral density, allow you to do a number of things that would otherwise be impossible. By reducing the amount of light, you can record movement in subjects such as waterfalls, clouds, cars, etc. You can also drop your aperture to allow a wider focus, helping separate subjects from their background. This filter offers a wide range of up to 8 stops of light.|Smooth Adjustable Dial|Multi-coated optics|Allows use of fast film in bright light|Perfect for motion blur and selective focus"