6nm H-Alpha 36mm Round Mounted CCD Filter

The Astronomik 6nm H-Alpha 36mm Round Mounted CCD Filter is an extremely narrow emission-line filter designed for precision H-alpha imaging of hydrogen-rich nebulae with CCD cameras. With a 6nm full width at half maximum (FWHM), it isolates H-alpha light at 656nm while blocking virtually all other wavelengths, delivering exceptional contrast between emission nebulae and the night sky. The filter completely suppresses light pollution from mercury and sodium vapor lamps, making it ideal for imaging from light-polluted sites, and it comes pre-mounted in a low-profile 3mm cell compatible with filter wheels. Note that this filter is strictly for CCD astrophotography and must never be used for visual or solar observation.