The Baader 1.25" Ultra-Narrowband 3.5nm H-Alpha Filter offers high contrasted images to about 656.3 nm in red spectral range. The H-Alpha Filter offers sharper details of nebulae and the star appearance are diminished even stronger.
This H-alpha filter has an anti-reflective coating to avoid ghosting of the images for clear and sharper images. It is designed for fast optical system ranging from F10 - F3.5. Along with its 2 mm of thickness, this filter is planeoptically polished and has non-ageing sealed coated edges.
In general this DeepSky Ultra-Narrowband H-alpha Filter is not suitable for solar observation. The Halfbandwidth of 3.5nm equals 35 Angstroem, high-quality H-alpha solar filter from Solar-Spectrum start at 0.8 Angstroem. At favorable conditions experiments might still be possible, although at lesser quality.
2 mm Thickness
Non-Ageing Sealed Coated Edges
Optical System Ranging From F10-F3.5
Manufacturer: Baader Planetarium
Coating: Dielectrically Coated and Planeoptically Polished