The Hoya PRO ND200 ND Filter is an important tool for controlling light reduction. This ND filter permits less depth of field under bright lighting since the aperture has to be larger and, in addition, it permits long time exposures in bright sunlight. The ACCU-ND technology in the Hoya PRO ND filters yields a truly neutral colour balance that will not add any noticeable colour-cast to your images. The Hoya PRO ND series is aimed at the still photography and HDSLR video markets. The Hoya PRO ND200 ND Filter reduces light entering the camera lens by the equivalent of 7 2/3 stops. The Metallic ACCU-ND coating on the PRO ND200 ND filters does not colour shift as you move from one density to the next, a common problem with other series of neutral density filters. Now you can set your white balance once and have the same colour balance even if you need to change filters due to changes in lighting, or for creative effect. The PRO ND filters use Hoya’s exclusive clear optical glass that has a metallic ACCU-ND coating front and back to create the neutral density effect. The Hoya PRO ND200 ND Filter is an extremely dark neutral density filter with a filter factor of 200. This filter factor converts to a 7 2/3 stops reduction on the amount of light entering the lens. With this extreme filter, motion is greatly blurred or depending on the speed some moving subjects will disappear altogether. With an ND filter as strong as the PRO ND200 shutter speeds as slow as 4 seconds or more are possible in daylight.