ALFHALW2

FHALW-2

Alpine Astronomical

This 2" Baader H-alpha 20nm Bandpass Filter from Alpine Astronomical is a high-contrast deep-sky, H-alpha/red filter for RGB astroimaging with CCD and CMOS cameras and telescopes of all focal ratios. The filter allows high-contrast images of H-II regions, even in light-polluted areas. UV/IR blocking eliminates blurring or heat-noise from defocused light on refractor optics.None Increased contrast, matched for typical CMOS quantum efficiency and s/n ratio Reflex-Blocker coatings, for freedom from halos, even under most adverse conditions concerning aux-optics 6mm low-profile filter cell Identical filter thickness to existing standards, with utmost care for parfocality Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim, to additionally eliminate any reflection due to light falling onto the edge of a filter Each filter coated individually, with sealed coating edge Life-Coat hard coatings to enable a non-aging coating for life, even in adverse environments