Designed for night scape photography, the HOYA STARSCAPE filter reduces light pollution generated by artificial lights common in cities. The HOYA STARSCAPE cuts light transmission in the area of the s espandi...pectrum that is usually associated with light pollution from Sodium and Mercury-vapor lights common to most cities world-wide. Thus, the filter provides a more clear image with natural colors and improved contrast in the night sky. The filter cuts off in the most natural way the transmission of light spectrum that is frequently presented in city environments and usually associated with Sodium and Mercury-vapor lights. MAIN FEATURES: Reduces yellowish and greenish color cast from artificial city lights. Natural color reproduction and improved contrast overall. Compatible with wide and super-wide angle lenses. Low profile frame. PRECAUTIONS Light pollution cut filter HOYA STARSCAPE does not cut 100% of light coming from Sodium and Mercury-vapor lights. Polluted light is a mixture of different unwanted light spectrums. HOYA STARSCAPE filter cannot cut all the polluted light spectrums.