The Tiffen 4 x 5.65" 0.3 Hard Edge Graduated Neutral Density (vertical orientation) filter is a graduated neutral density filter that helps to specifically darken skies and other bright areas of the image. nnThe filter is denser at the edge and fades towards the middle, with a sharp transition line between the density area and the clear area. Neutral density filters do not affect the colouration of the image and the 0.3 density provides a one-stop reduction of light entering the lens.nnThis filter is constructed from Water White glass and manufactured using ColorCore technology, a process that involves laminating the filter substrate between 2 pieces of optical glass and polishing it flat to a tolerance of 1/10,000th of an inch. This filter measures 4 x 5.65" / 101.6 x 143.5 mm. nn-0.3 Hard Edge graduated ND filter to darken skies and other bright areas of the image.n-Provides a one-stop reduction of light in selective areas.n-Neutral density filters do not affect the overall colouration of the image.n-Water White optical glass for excellent clarity.