Features: Baader 3.5-4nm Ultra-Narrowband 31mm CMOS optimized H-alpha O-III S-II Filterset
- 31 mm x 2 mm Baader H-alpha / O-III / S-II Ultra-Narrowband Filter Set – Premium Grade
- 3.5 / 4 nm FWHM (to harmonize the exposure time from H-alpha 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 telescope-sided black outer rim
- Optimized for modern CMOS cameras, but likewise excellent for CCD camera technologies
- Increased contrast
- Evermore narrow passbands
- Reflex-Blocker™ coatings, for largest-ever freedom from halos, even under most adverse conditions concerning aux-optics
- FWHM on each filter category carefully designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio
- Identical filter thickness to existing standards, with utmost care for parfocality
- Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim, to additionally eliminate any reflection due to light falling onto the edge of a filter
- Each filter is coated individually, with a sealed coating edge (NOT cut out of a larger plate with coatings left exposed)
- Life-Coat™: evermore hard coatings to enable a non-aging coating for life – even in a most adverse environment
Specifications: Baader 3.5-4nm Ultra-Narrowband 31mm CMOS optimized H-alpha O-III S-II Filterset
- MANUFACTURER Baader Planetarium
- SKU (#) 2961671
- EAN CODE 4047825104045
- NET WEIGHT (KG) 0.18
- COLOUR Black
- TRANSMISSION RANGE H-alpha / O-III / S-II
- FILTER THICKNESS (WITHOUT CELL) 2 mm
- HBW (HALFBANDWIDTH) 3.5 nm (H-alpha) / 4 nm (O-III / S-II)
- CWL (CENTRAL WAVELENGTH) 656,3 nm / 500,7 nm / 671,7 nm
- AR-COATING Reflex-Blocker™ hard-coated, plane optically polished
- SPECIAL FEATURES CMOS-optimized with Life-Coat™
- FILTER SIZE 31 mm
- FILTER USAGE CMOS, CCD, H-alpha, O-III, S-II
- FILTER MOUNTED Unmounted
- TYPE OF FILTER Ultra-Narrowband
- SINGLE OR SET? Filter-Set
- FILTER SHAPE round
Kit content
Baader 3.5-4nm Ultra-Narrowband 31mm CMOS optimized H-alpha O-III S-II Filterset
Filter cleaning cloth
Filter box
User guide
For more information about, Baader 3.5-4nm Ultra Narrowband 31mm CMOS optimized H-alpha O-III S-I website.
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