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Baader CMOS-optimized S-II Highspeed Filter (6.5nm) - 1.25"

SKU : BA-FCSIIHS-1

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  • Highspeed, CMOS-optimized filter provides increased contrast with super narrow passbands
  • 6.5nm FWHM is recommended for extremely fast optical systems from f/3.4 to f/1.8, such as the Celestron RASA astrographs
  • Advanced filter coating technology exclusive from Baader, including Reflex-Blocker™ hard-coatings to prevent halos and Life-Coat™ prevent wear-and-tear from usage
  • Best when used with modern CMOS cameras, but can still be used with CCD cameras to produce beautiful results
  • This part# only includes one (1) SII filter and not the Ha or OIII filters pictured

Product Details

  • Baader's CMOS-optimized Filters

    Behold the latest and greatest development in the world of astro filters - the CMOS-optimized Highspeed filters from Baader! These filters help tackle the issue of unbearable halos when put into close vicinity of correcting lenses, in conjunction with the latest generation of CMOS-chips. All at a reasonable price point!

    When the revolutionary CMOS-chips starting hitting the camera markets, there were many issues with people experiencing halos whenever a coma-corrector, field-flattener, or reducer-corrector would be placed in close proximity to the "older", more CCD-centric filters. Baader took the time to study how this could be fixed most cost-effectively to ensure that all amateur astrophotographers would have access to the same technology. All of this research and development lead to the creation of Baader's Reflex-Blocker™ coating systems.

    To all of you that are still using other digital camera technologies besides CMOS -- don't fret! You can still benefit from the advanced capabilities of the CMOS-optimized filters, whether you use CCD or CMOS. However, owners of CCD-cameras will still find that the previous generation of Baader's narrowband filter technology to work for excellent imaging.

    Features of CMOS-optimized Filters

    The new generation of CMOS-optimized filters will provide you with increased contrast in your images with ever-more narrow passbands. The FWHM on each filter category was carefully designed to allow for 1:1:1 exposures, which is perfectly matched for typical CMOS quantum efficiency and s/n ratio. These filters have an identical filter thickness to existing standards and uphold a high standard of care for parfocality. With blackened edges all around, including filter-lead-side-indicator in the shape of a black frontside outer rim, you'll be sure to eliminate any additional reflection that is caused by light falling onto the outer edge of your filter. Even better, each filter is coated individually, meaning that they are NOT cut out of a larger plate with coatings left exposed.

    Life-Coat™

    Baader is offering an exclusive, limited-lifetime-warranty on their new CMOS-optimized filters! Filters that have Baader Planetarium's Life-Coat™ technology are so durable that Baader warrants the coatings for the life of the filter. Life-Coat™ was developed by Baader using materials and processes that result in coatings that will not degrade or fail for a lifetime. These coatings resist moisture, temperature extremes, and are hardened to withstand normal cleanings. Therefore, these filters will not peel, flake, or physically degrade and can handle repeated cleaning with fine optical cleaning equipment. This Limited Lifetime Warranty applies to the original purchaser and does not cover failure from misuse, physical damage through improper handling, or improper cleaning methods. Read more about Baader's filters and filter cells. 

  • specifications

    Bandpass6.5nm
    Filter ShapeRound
    Filter Size1.25"
    Filter TypeSII
    Free ShippingYes
  • included items

    • Highspeed, CMOS-optimized filter provides increased contrast with super narrow passbands
    • 6.5nm FWHM is recommended for extremely fast optical systems from f/3.4 to f/1.8, such as the Celestron RASA astrographs
    • Advanced filter coating technology exclusive from Baader, including Reflex-Blocker™ hard-coatings to prevent halos and Life-Coat™ prevent wear-and-tear from usage
    • Best when used with modern CMOS cameras, but can still be used with CCD cameras to produce beautiful results
    • This part# only includes one (1) SII filter and not the Ha or OIII filters pictured

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