Baader Planetarium 4.5nm Sulfur-II Ultra-Narrowband CCD Filter, 2" Eyepiece

SKU: AAFSIINU2 MFR: FSIINU-2
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Key Features

  • Capture stunning deep-sky images with this 2" Baader Planetarium S-II narrowband filter.
  • Enhance your astrophotography with the 4.5nm ultra-narrowband filter, perfect for CCD imaging.
  • Experience superior contrast with this high-quality telescope filter, blocking unwanted light.
  • Achieve pinpoint stars using our plane-optically polished, dielectrically coated 2" eyepiece filter.
  • Explore the cosmos with confidence; this durable filter has a precise 673 nm central wavelength.
  • Easily install this mounted filter; it's designed for 2" eyepieces and delivers optimal S-II transmission.
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Special Order?Estimated to Ship: 09/10/2025
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Baader Planetarium Narrowband Filter Specifications

  • Transmission range

    S-II

  • Filter thickness (without cell)

    2mm / 3mm

  • HBW (half bandwidth)

    4.5nm

  • CWL (central wavelength)

    673 nm

  • AR-coating

    Dielectrically coated, plane-optically polished

  • Filter usage

    CCD, IR-Cut, S-II

  • Filter mounted

    Mounted

  • Filter Size

    2" Eyepiece

  • Weight

    0.07kg (0.15 lbs)

About Baader Planetarium Narrowband Filter

Become an astrophotography enthusiast with the 4.5nm Sulfur-II Ultra-Narrowband CCD Filter, designed for 2" eyepieces. This premium-grade Baader Sulfur II (S-II) filter is specifically engineered for use with fast optical systems, compatible with focal ratios ranging from f/3 to f/8.

The filter's ultra-narrowband 4.5nm design ensures high-precision light transmission, capturing the most intricate details in your celestial photography. It is IR-blocked, effectively reducing infrared interference for clearer, sharper images.

Further enhancing your astrophotography experience, the filter boasts anti-reflection coatings. This feature minimizes light scattering, eliminating halos and ghosting from your images for a more accurate representation of the night sky.

Designed for longevity, the filter features non-ageing sealed coated edges. This ensures the filter's durability and performance, providing you with high-quality, clear images for years to come.

Whether you're a seasoned astrophotographer or just starting out, the 4.5nm Sulfur-II Ultra-Narrowband CCD Filter for 2" eyepieces is a valuable addition to your equipment, enhancing your ability to capture the beauty of the cosmos.

Baader Planetarium Narrowband Filter Features

  • For fast optical systems from f / 8 to f / 3
  • Reflection-free, anti-reflective and smooth-surfaced
  • IR-blocked
  • NO halos, NO reflections, NO ghosting
  • Non-ageing sealed coating edges

Warranty Information

This product has a limited warranty of 24 months for parts and 24 months for labor.

Key Features

  • Capture stunning deep-sky images with this 2" Baader Planetarium S-II narrowband filter.
  • Enhance your astrophotography with the 4.5nm ultra-narrowband filter, perfect for CCD imaging.
  • Experience superior contrast with this high-quality telescope filter, blocking unwanted light.
  • Achieve pinpoint stars using our plane-optically polished, dielectrically coated 2" eyepiece filter.
  • Explore the cosmos with confidence; this durable filter has a precise 673 nm central wavelength.
  • Easily install this mounted filter; it's designed for 2" eyepieces and delivers optimal S-II transmission.

What's in the box:

  • Baader Planetarium 4.5nm Sulfur-II Ultra-Narrowband CCD Filter (2 " Eyepiece)
  • Alpine Astronomical Baader Stackable Filter Box
  • Baader Planetarium 2 Year Limited Warranty