2" x 2 mm Baader H-alpha Ultra-Narrowband Filter – Premium Grade – with 2" (M48) filter thread
3.5 nm FWHM (to harmonize the exposure time with O-III / S-II), recommended for optical systems from f/10 to f/3.5
For highest contrast even at strongest light pollution, minimizes star size, emphasizes finest nebula detail – indispensable under Bortle 9/8/7/(6) skies
Reflex-Blocker™ hard coated and plane optically polished – with sealed coating edges (Life-Coat™)
Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim
Optimized for modern CMOS cameras, but excellent for CCD camera technologies
Mounted in Baader Low Profile Filter Cell (LPFC) – 6 mm height
Specifications:
Manufacturer: Baader Planetarium
SKU (#): 2961328
EAN CODE: 4047825047571
Colour: Black
Transmission range: H-alpha
Filter thickness (WITHOUT CELL): 2 mm
HBW (HALFBANDWIDTH): 3.5 nm
CWL (CENTRAL WAVELENGTH): 656,3 nm
AR-Coating: Reflex-Blocker™ hard coated, planeoptically polished