3nm Narrowband Sulfur II - 2" Mounted

The Antlia 3nm Narrowband Sulfur II filter is an ultra-narrow bandpass filter optimized for imaging sulfur-II (SII) emission at 671.6nm in nebulae, planetary nebulae, and supernova remnants. With a 3nm FWHM bandwidth and 88% peak transmission, this filter delivers exceptional contrast with minimal light pollution interference while maintaining excellent signal-to-noise ratio with OD5 (0.001%) out-of-band blocking. The filter is compatible with optical systems as fast as f/3 and is part of the popular Hubble SHO color palette when combined with H-alpha and OIII filters.