Star filters generate multiple points of light, or “stars,” streaking outward from a central light source. Outcome of lighting within the scene takes on a more sparkling, alluring appearance. This effect is produced by a series of thin lines etched into the flat optical surface of the clear filter.
Lines in one direction produce an eight-pointed star, just a streak through the center of the light. Generally, mid-range or larger apertures are sufficient to attain a good star effect.
Material Construction: High definition optical glass
Star filters are one of must haves for both digital and film photography. Why? Because bright source of light is portrayed by flairs, rays universally across cultures (remember how children draw a sun?). At the same time on a photo, or even on a slide, a bright source of light is just a white spot. Star filters are used to translate brightness of the sun, blinks of light on the water, reflections, etc. into a culturally readable image. A Star filter is a must. Period. Most professionals have star filters, not UV filters, permanently mounted on their photo and video equipment.