Optimized for use on fast astrographs for astrophotography and imaging, the Alpine Astronomical Baader f/2 Highspeed H-alpha Filter isolates this narrow 656.3nm wavelength to improve the visibility and contrast of faint and wispy nebulae, even in heavily light-polluted areas. This filter is ideal when used on Celestron's Rowe-Ackermann Schmidt Astrograph (RASA), or with Hyperstar-equipped Cassegrains.
When conventional narrow-band filters are used on fast optical tube assemblies, there is usually significant transmission loss due to strong center-wavelength shift. To counter this, the Highspeed H-alpha filter is designed to be pre-shifted to bring them back on band when used with f/2 to f/3 optical systems. The filter surface is dielectrically coated with anti-reflection coatings to transmit the maximum amount of light throughput, and precision planeoptically polished to limit distortion and color fringing. This version of the filter is offered here mounted in a standard 1.25" filter ring assembly for easy installation on just about any 1.25" eyepiece, diagonal, or Barlow lens for prime-focus or eyepiece projection photography and imaging techniques.
This filter is intended only for deep-sky astroimaging and photography equipment, and should never be used for direct solar viewing or solar photography as permanent injury to your eye and equipment can occur, up to and including blindness.