Description
This 2" Baader H-alpha Narrowband Filter from Alpine Astronomical is a 6.5nm FWHM filter recommended for optical systems from f/10 to f/3.5. It features a Reflex-Blocker hard coating, which has been plane optically polished, and has Life-Coat sealed edges. It is equally suitable for modern CMOS sensors as well as older CCD camera technologies.None Reflex-Blocker coating for freedom from halos, even under most adverse conditions concerning aux-opticsIdentical filter thickness to existing standards, with utmost care for parfocalityBlackened edges with filter-lead side-indicator in the form of a black frontside outer rim to eliminate reflection due to light falling onto the edge of a filterEach filter is individually coated, with sealed coating edge (not cut out of a larger plate with coatings left exposed)Life-Coat evermore hard coatings are non-aging for life - even in adverse environments