The Tiffen 4 x 5.65" 6-point/4 mm glass star effect filter creates multiple light points, or "stars", extending 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 etched onto the flat optical surface of a clear filter. The size and brightness of the star lines produced are primarily a function of 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 1 mm to 4 mm - A 1 mm spacing has twice as many lines as a 2 mm 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-pointed star effects as well as additional asymmetric star patterns through their exclusive Hollywood FX series (North, Hyper, Vector and Hollywood star effects) - With an 8-pointed filter, the many star lines can tend to dominate the rest of the image, so use it with caution - Generally, medium or wider apertures are sufficient to achieve a good star effect; Always test before critical situations Specifications