The Astronomik H‑alpha 6 nm CCD 27 mm Filter (without frame) (SKU: 10212527 / 8h00mk) is a high‑quality narrowband filter designed for astrophotography of emission nebulae. It only allows light from the hydrogen line (656 nm) to pass through, blocking other wavelengths, allowing for high‑contrast images even in light‑polluted conditions.

Key Features

• central wavelength: 656 nm (H‑alpha)
• bandwidth (FWHM): 6 nm
• transmission: typical 96%, guaranteed >90%
• broad UV and IR blocking
• filter thickness: 1 mm
• no focal shift – parfocal filters with other Astronomik filters
• MFR coating – full compatibility with optical systems with a light intensity of f/4 to f/∞ without significant transmission losses

Set components

• Astronomik H‑alpha 6 nm CCD 27 mm filter (unmounted)

Technical parameters

• diameter: 27 mm (without frame)
• FWHM: 6nm
• transmission: >90% (typically 96%)
• material: optical glass, thickness 1 mm
• compatibility: optical systems from f/4 to f/∞ (MFR)
• resistance: to moisture and scratches