The bandwidth of Svbony CLS filters is wider than that of Svbony UHC filters, and the luminous flux is large, which is more suitable for use in places with less light pollution.
The Svbony City Light Suppression broadband filter is designed to improve the visibility of various Deep sky objects. By selectively reducing the transmission of wavelengths of light pollutants, specifically those produced by artificial lightings including mercury vapor lamps, both high & low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow)
Together with high transparency in main nebula emission lines at O-III (496nm and 500nm), H-beta (486nm), N-II (654nm and 658nm), H-alpha (656nm) as well as S-II (672nm), the Svbony CLS filter is suitable for enhancing the contrast and details for both visual and photographic purpose in urban areas.
Light pollution filter do not eliminate the effects of light pollution or increase the object's brightness. In many cases, they increase the contrast between nebula and night sky, not brightening the nebula.