The Schneider Optics 4" x 4" ND 0.9 S Square Filter is a professional neutral density filter engineered to provide precise exposure control for motion picture and broadcast cinematography. With an optical density of 0.9, this filter reduces light transmission by three f-stops, allowing cinematographers to maintain wider apertures for shallow depth of field or achieve specific shutter angles for creative motion effects in bright lighting conditions. The "S" designation indicates a soft-edged graduated filter, where the transition between the clear and ND portions is gradual, making it ideal for balancing exposure between bright skies and darker foregrounds when the horizon line is irregular or when using shorter focal length lenses. Crafted from Schneider's precision water-white optical glass, this filter is diamond-cut and ground to exceptional flatness with verified plane-parallelism, ensuring no image degradation when placed in front of the finest lenses. Both surfaces feature Schneider's hard anti-reflective (AR) coating, reducing light loss to less than 1% per surface while resisting flaking, peeling, and scratching during demanding production use. The 4 x 4-inch industry-standard size fits all professional matte box systems and includes a protective case for secure storage and transport between shoots. Each filter is individually tested with densitometers and spectrophotometers for consistent density and light transmission, allowing cinematographers to swap like filters mid-shoot with no discernible variation. Read more

Features