The Hitech 72mm Multistop Neutral Density Filter is a solid variable neutral density filter providing a reduction of about 1 to 6 stops of exposure. The 0.3 to 1.8 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed than normally required. The degree of density is easily controlled by rotating the front filter ring, allowing you to previsualize the additional exposure length required. By slowing your exposure time or increasing your aperture, you are able to control depth of field and convey movement more easily. Neutral density filters do not affect the coloration of the image.
This filter features a large front rotating element to help reduce vignetting when used with wide angle lenses. It is constructed from specially formulated CR-39 resin sandwiched between two layers of high-quality Schott glass and has an aluminum filter ring.