【Light pollution reduction & constellation accentuation】While suppressing the color tint caused by sodium-vapor lamps, mercury lamps, etc., the filter brings the light of the bright stars through, accentuating the constellations. 【Effect1. Light pollution-cutting effect to restrain color casts caused by city lights.】Sodium-vapor and mercury lamps and other streetlights cause yellow and orange color casts in the night sky, but Starry Night Prosofton cuts out only the light of specific frequencies that correspond to these colors, allowing for natural color reproduction. 【Effect 2. Soft effect to make the constellation picture stand out while the landscape and background remain clear.】The softening effect is applied only to point light sources such as stars, and does not affect the surrounding scenery, making it suitable for starry landscapes or when you do not want to apply softening effects to anything other than stars. 【Works perfectly with wide-angle lenses】 Since two effects can be achieved with a single filter, it eliminates the need for stacking filters and reduces the risk of vignetting and flare. Filter diameter: φ72mm / Made in Japan