The Tiffen 6.6 x 6.6" 6-Point/4mm Star Effect Glass Filter creates multiple light points, or "stars", which extend outwards from a central light source. This can give scene lighting a more sparkling and glamorous appearance. This effect is produced by a series of fine lines engraved on the flat optical surface of a clear filter. The size and brightness of the star spikes produced depend primarily on the size, shape and brightness of the light source. - You have additional control through the choice of a particular spacing between the filter lines; these spacings are measured in millimetres and range from 1mm to 4mm - A 1mm spacing has twice as many lines as a 2mm spacing; it will produce a brighter star for a given source - Lines in one direction produce a two-pointed star, just a streak across the centre of the light - Tiffen offers symmetrical 4-, 6- and 8-point star effects as well as additional asymmetric star patterns through its exclusive Hollywood FX series (North, Hyper, Vector and Hollywood star effects) - With an 8-point filter, the many star spikes can tend to dominate the rest of the image, so use with care - Generally, medium or larger apertures are sufficient to achieve a good star effect; always test before critical situations Specifications