Lumicon 2 Inch Gen3 UHC Filter (2nd Quality)2nd Quality Filters have small defects that do not significantly affect performance Lumicon 2 Inch Gen3 UHC Filter Lumicon 2 Inch UHC Filter is unbeatable for revealing nebulosity. This is achieved by passing three nebula emission lines the two doubly ionized oxygen lines (496 and 501nm) and the H beta line (486nm) while blocking light pollution and Sky Glow. The result is superb views of the Orion, Lagoon, Swan and other extended nebulae. Lumicon