The Formatt-Hitech 5.65 x 5.65" Soft Edge Graduated Neutral Density 0.6 Glass Filter helps to specifically darken skies and other bright areas of the image. The filter is densest at the edge and fades to clear in the middle, with a soft edge transition line between the density areas and the clear areas. By having only a neutral density portion on the filter, you can selectively darken areas of an image whilst allowing the part of the image in the clear section to receive the normal amount of exposure. Neutral density filters do not affect image colouration and the 0.6 density provides a 2-stop reduction in the light entering the lens. Formatt-Hitech glass filters are manufactured from high-quality Schott Superwite glass for exceptional clarity and maintained light transmission. This filter measures 5.65 x 5.65" / 143.5 x 143.5 mm. - Soft edge graduated ND 0.6 filter to darken skies and other bright areas of the image. - Provides a 2-stop reduction in light in selective areas. - The soft edge transition is ideal for situations where there is no distinct separation line between light and dark areas of the image. - Neutral density filters do not affect the overall colouration of the image.