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OPTOLONG 1.25inch Filter SII-CCD 6.5nm Narrow-Band Filter for Telescope
OPTOLONG 1.25inch Filter SII-CCD 6.5nm Narrow-Band Filter for Telescope
OPTOLONG 1.25inch Filter SII-CCD 6.5nm Narrow-Band Filter for Telescope
OPTOLONG 1.25inch Filter SII-CCD 6.5nm Narrow-Band Filter for Telescope

OPTOLONG 1.25inch Filter SII-CCD 6.5nm Narrow-Band Filter for Telescope

$ 83.95

Availability: 100 in stock
  • All returns accepted: Returns Accepted
  • Compatible Brand: Universal
  • Condition: New
  • MPN: Does Not Apply
  • Brand: Optolong
  • Item must be returned within: 30 Days
  • Type: filter
  • Return shipping will be paid by: Buyer
  • Restocking Fee: No
  • Country/Region of Manufacture: China
  • Refund will be given as: Money Back

    Description

    OPTOLONG 1.25 inch Filter SII-CCD 6.5nm Narrow-Band Filter for Astronomy Telescope Deep Sky 1.25" Mounted
    The Optolong 1.25" Filters are made with Schott glass that has been multi-coated with an ion-assisted deposition technology to ensure scratch resistance and stability on the central wavelength, or CWL. The filter cell is made of lightweight, strong metal and is CNC machined, sand-blasted; black anodized, and then laser engraved. The result is a super thin filter cell that will produce a clear aperture of 26mm.
    The Optolong Sulfur II 6.5nm Extra Narrowband Filter transmits a 6.5nm bandwidth of light that is centered at 672nm and drastically reduces other transmissions, including wavelengths of light that are responsible for light pollution (both artificial and natural). Like all Optolong filters that are designated as" CCD", this SII filter also blocks infrared wavelengths from 700nm to 1100nm so you don't need a separate IR-Cut filter.
    Quality Filter Materials:
    Schott B260 substrate material from Germany, 2.0mm thick
    CNC machined and black anodized aero-metal filter cell that is ultra-thin to provide largest clear aperture; Laser-engraved to prevent fading
    Multiple layers of anti-reflection non-cementing coatings applied via electron-beam gun evaporation with Ion-assisted deposition
    Filter Manufacturing Processes and Parameters:
    Filter substrate is fine-optically polished to 1/4 wave and <30 parallelism over both surfaces
    Surface quality, according to MIL-O-13830, is 60/40
    80% transmission at SII line 672nm
    Infrared wavelength 700-1100nm cut-off
    0.1% transmission Hg at 435nm and 578nm
    0.1% transmission Na at 589nm
    High value transmission of pass-band and optical density of off-band is assured through Optolong's planetary rotation system, a homogenous and precise coating procedure
    Thin metal cells have a clear aperture of 26mm for 1.25" filters
    Each filter comes with a plastic case with high pressure EVA case lining
    Packageing:
    OPTOLONG 1.25 inch SII 6.5nm Filter
    Plastic Cases