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Chroma SII 3nm Narrowband Filter - 50mm Square

SKU : CF-SII-673-3-50S

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  • Made in America
  • Filter sizes up to 2-inch & 50 mm Square without T-thread or SCT thread come with a complimentary TPO Filter Case (OS-CF2) to keep your filter safe.
  • Built for fast telescopes and equipment able to fit 50x50mm filters.

Product Details

  • Please Note:The interference coatings that optical filters are made with are angle-sensitive and shift to the blue with fast focal ratios. This is not a problem for filters 5nm or wider, but the 3nm filters shift enough to compromise transmission at the wavelength line of interest. Chroma has made a set of Ha, OIII and SII 3nm that are optimized for F/3 beams by moving the center wavelength slightly into the red so they will shift slightly to the blue when used in an F/3 beam, thus maximizing transmission at the nominal wavelength. For beams faster than F/3, we recommend using 5nm-wide or wider bands.

    This Narrowband filter by Chroma is expertly designed for a precise, limited wavelength acceptance of 3nm for SII. 

    Built for fast telescopes and equipment able to fit 50x50mm filters.

  • specifications

    Bandpass3nm
    Filter ShapeSquare
    Filter TypeSII
    Free ShippingYes
    Size50mm
  • included items

    • Made in America
    • Filter sizes up to 2-inch & 50 mm Square without T-thread or SCT thread come with a complimentary TPO Filter Case (OS-CF2) to keep your filter safe.
    • Built for fast telescopes and equipment able to fit 50x50mm filters.

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