Svbony SV240 Multi-Narrowband filter (2")

The Svbony SV240 Multi-Narrowband Filter is designed specifically for amateur astronomers photographing in urban light-polluted environments, and the manufacturer says it works well under Bortle 8 skies

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When used with standard astronomy cameras or DSLR, MILC cameras, the effect of multiple narrowband filters can be achieved in a single shot using a single filter. As a result, light pollution is 99% blocked, with only three wavelength ranges, H-beta, OIII and H-alpha, showing up in astrophotographs. In these ranges, its 90%+ transmittance rivals similar products from more well-known brands.