SVBONY SV132 Telescope Filter, 2 inches H-Beta Narrowband Filter, 25nm Visual Nebulosity Eyepiece Filter, for Horsehead Nebula California and Cocoon Nebulae in Dark Skies
- Mainly aimed at the 486nm (blue) line spectrum nebula.
- filters out the interference of other light.
- the Horsehead Nebula can be clearly seen.
- filter with metal mount 2" filter threads.
- threaded to fit 2" eyepieces and threaded diagonal barrels.
- needs to be observed with a large-aperture telescope.