The 1.25" Baader 6.5nm Narrowband Filter Set from Alpine Astronomical features three precision-grade filters designed for f/10 to f/3.5 optical systems. The set includes H-alpha, O-III, and S-II filters optimized for CMOS sensor cameras and also suitable for CCD sensors.
H-alpha, O-III, and S-II narrowband filter set
6.5 nm FWHM recommended for optical systems from f/10 to f/3.5
Designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio
Reflex-Blocker hard coated and planoptically polished — with sealed coating edges (Life-Coat)
Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim
Optimized for CMOS cameras and suitable for CCD cameras
Increased contrast
Narrow passbands