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Baader 3.5 / 4nm f/3 Ultra-Highspeed Filters – CMOS-optimized (H-alpha / O-III / S-II)

Baader 3.5 / 4nm f/3 Ultra-Highspeed Filters – CMOS-optimized (H-alpha / O-III / S-II)

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Baader 3.5 / 4nm f/3 Ultra-Highspeed Filters – CMOS-optimized (H-alpha / O-III / S-II) - Astronomy Plus

Baader 3.5 / 4nm f/3 Ultra-Highspeed Filters – CMOS-optimized (H-alpha / O-III / S-II)

Regular price $219.99
Regular price $219.99 Sale price $301.35
SAVE 26% Sold out
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Baader 3.5 / 4nm f/3 Ultra-Highspeed Filters – CMOS-optimized (H-alpha / O-III / S-II)

  • Baader H-alpha / O-III / S-II f / 3 Ultra-Highspeed Filter Set - Premium Grade
  • 3.5 / 4 nm half width (to harmonize the exposure time of H-alpha with O-III / S-II), recommended for extremely fast optical systems from  f/3.4 to f/2.3
  • Specially designed for the special filter requirements when used with fast f/3 optics
  • Enables the highest contrast even with the strongest light pollution, minimizes the size of the stars, makes the finest nebula details accessible - indispensable under Bortle 9/8/7/(6) sky
  • Reflex-Blocker ™ hard-coated and optically polished - with sealed coating edges (Life-Coat ™)
  • Blackened edges all around, with a filter front indicator in the form of a black outer edge on the front
  • Optimized for modern CMOS cameras, but ideally suited for CCD camera technologies

The new generation of Baader CMOS-optimized filters features:

  • CMOS-Optimized Baader Filter
  • Increased contrast
  • Ever more 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 coated individually, with sealed coating edge (NOT cut out of a larger plate with coatings left exposed read more)
  • Life-Coat™: evermore hard coatings to enable a non-aging coating for life – even in a most adverse environment

Technical Specifications


MANUFACTURER Baader Planetarium
SUITABLE FOR F/RATIO < f/2.3
TRANSMISSION RANGE H-alpha / O-III / S-II
FILTER THICKNESS (WITHOUT CELL)

2 mm Thickness = 1.25"/ 2" / 31mm / 36mm

3mm Thickness = 50.4mm / 50x50 / 65x65

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, planeoptically polished
SPECIAL FEATURES CMOS-optimized with Life-Coat™
FILTER SIZE Multiple
FILTER USAGE CMOS, CCD, H-alpha, O-III, S-II
FILTER MOUNTED Mounted (LPFC 6mm) / Unmounted 
TYPE OF FILTER f/2 Ultra-Highspeed
SINGLE OR SET? Singles and Filter-Set
FILTER SHAPE round / square (depending on size)

 


In the Box

  • Baader 3.5 / 4nm f/3 Ultra-Highspeed Filters

      Warranty & Manuals

      Baader Limited Lifetime Warranty

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