Optolong L Ultimate 2 Dual Bandpass Light Pollution Reduction Imaging Filter

Introduction: It'S About A 3Nn Dual Band Designed To Drastically Reduce The Effect Of Light Pollution, The 3Nm Isolates The Nebulae'S Emissions Into H-Alpha (Red) And Olll (Green-Blue). It Blocks Light Pollution, Maximizes The Signal From Nebulae, And Darkens The Sky Background. It Also Blocks Artificial Light From Mercury Vapor Lamps, High And Low Pressure Sodium Vapor Lights, And Unwanted Natural Light Caused By The Emission Of Neutral Oxygen In Our Atmosphere. Maximizes The Transmission Of The Main Emission Lines Of The Nebula In Olli (496Nm And 500Nm) And H-Alpha (656Nm). Used With Dsl, Color/Mono Cmos And Ccd, However, This Filter Is Not Suitable For Fast Ratio Systems.