All-Star Telescope is the best place to get Optolong filters.
Optolong was founded in 1999, and has become one of the world's premiere developers and manufacturers of astrophotography filters. Optolong offers a great selection including narrowband (H-Alpha, SII, OIII, LRGB) in 3nm and 7nm options, broadband filters (CLS, CF), and Dual-Band (L-Extreme and L-Ultimate).
Optolong has everything you need to get the shot just right.
