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Baader CMOS-optimized S-II f/2 Ultra Highspeed Filter (4nm) - 47.4mm

SKU : BA-FCSIIHSU-2U

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  • CMOS-Optimized
  • Increased contrast
  • More narrow passbands
  • Reflex-Blocker™ coatings
  • FWHM on each filter
  • Blackened edges
  • Life-Coat™

Product Details

  • The all-new CMOS-optimized filters work magnificently with all existing digital camera technologies, be it CMOS or CCD. However – an owner of CCD-camera-technology will still find our previous, extremely affordable, narrowband filter technology to be fully apt for excellent imaging.

    Now with 47.4 mm unmounted for use with FCCT

    • Baader H-alpha / O-III / S-II f / 2 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 / 1.8
    • Specially designed for the special filter requirements when used with highly opened optics such as the Celestron RASA astrograph
    • 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


  • specifications

    Bandpass4nm
    Filter ShapeRound
    Filter Size47.4mm
    Filter TypeSII
    Free ShippingYes
    MountingUnmounted
  • included items

    • Baader CMOS-optimized S-II f/2 Ultra Highspeed Filter (4nm) - 47.4mm

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