The lee sw150 neutral density 09 standard resin filter absorbs light evenly across the visible spectrum therefore reducing the light entering the lens without effecting colour balance nd filters extend exposure times allowing for movement in an image be it people water foliage or clouds if used with care the effects can be impressive using the 09 nd neutral density filter exposure can be controlled by 3 stops the filter measures 150 x 150 mm and is for use with the lee sw 150 filter h