Baader Planetarium 2 Inch Blue Eyepiece Filter

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Item #AAS091-1

  • Your Price:
  • $64.00

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  • 2" Format Eyepiece Filter
  • Blue Color Filter
  • 470nm Bandpass
  • 2mm thickness
  • Can be stacked with other filters
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  • Description

    Freedom from Ghost images, even when stacked.  Striae-free substrates are polished parallel to 30 seconds of to avoid wedge errors.  Finest 7-layer  hard multicoatings on both faces feature 0.25% residual reflections (Baader filters are unique, no other colored filter incorporates anti-reflection multicoatings).  The coatings are also different for each of the filters, in order to match the coating performance to the filter curve of each color.  This maximizes the transmission and minimizes reflections.


    Extremely High Transmissions result in maximum contrast and isolation of planetary details, even with smaller telescopes.  Efficiencies of the three longpass filters (Red, Orange, and Yellow) peaks at 98%, and efficiencies of the three bandpass filters (Green, Blue, Dark Blue) achieve 70%. 


    Carefully designed spectral characteristics.  Filters may be stacked without image degradation or ghosting, in order to provide even narrower passbands.  Or, combine with any of the other Baader filters for interesting possibilities.


    No reduction in sharpness, even at high magnifications or when using the filter far ahead of the focal plane (ie, digital imaging, or in front of a diagonal or binoviewer). 

    Supplier SKU


    Shipping Restrictions

    Only ships in contiguous USA.

  • Dimensions & Specifications


    Baader Planetarium


    2 Inches


    Planetary Filters


    2 Year Manufacturers Warranty

  • Product Guarantee

    We stand behind all the products we sell, and your satisfaction is our top priority. If you're not satisfied with the quality of your purchase, simply send the item back to us in its original packaging within 30 days of its delivery.

    Manufacturer Warranty

    This product has a 2 year manufacturer's warranty against defects is provided. If you have specific questions about this product's warranty please contact Alpine Astronomical's Customer Service department by email at

    Return & Exchange Policy

    At our site, returns are easy! You may return new, unused, and resalable items for a refund or exchange. Simply ensure that the item is returned in its original product packaging within 30 days of delivery.

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