Designed to virtually eliminate the appearance of stars, use the Alpine Astronomical Baader 3.5nm H-alpha Enforced-Narrowband Filter during long-exposure astrophotography and imaging to isolate this narrow band and improve the visibility and contrast of even the faintest and most wispy nebulae—even in heavily light-polluted areas.
This filter is ideally suited for optical systems from a fast f/3.5 to a more moderate f/10, including optical tube assemblies of all apertures and designs. The optical surfaces are dielectric anti-reflection coated and planeoptically polished to maximize light transmission with consistent and even throughput across the entire surface area. It is offered here mounted in an aluminum frame that has been threaded to fit standard 2" eyepieces and accessories for projection and afocal photography and is ideal for long-exposure astrophotography to produce composite images when stacked and matted with multiple exposures using multiple band filters.
This filter is intended only for deep-sky astrophotography, and should never be used for direct solar viewing or photography as permanent injury to your eye and equipment can occur, up to and including blindness.