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Astronomik SII 6 nm CCD Filter - 27 mm Round - SII6-27

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SKU: ASF-SII6-27

Astronomik SII 6 nm CCD Filter - 27 mm Round

  • This Astronomik SII 6 nm CCD Filter is a photographic filter in a 27 mm round format
  • Designed with the highest technical standards in mind to enable peak optical performance for deep sky imaging applications with your CCD camera
  • Ionized sulfur (SII) light is allowed to pass while the complete rest of the visual spectrum as well as IR is cut off
  • Approximately 6 nm FWHM bandwidth
  • An optimal fit for imaging planetary nebulae and supernova remnants
  • German-made for high optical quality!


More About Astronomik SII 6 nm CCD Filters

Astronomik SII 6 nm CCD Filters are the optimal solution for CCD astrophotography applications. Features a reduced 6 nm FWHM (full width at half maximum) combined with a typical 96% transmission for an incredible contrast enhancement since all spurious light from wavelengths other than the SII line (672 nm) is cut off from UV up to the IR. This provides a background that is extremely dark. Transmission losses and chromatic distortions, while an issue with other filters, only arise with Astronomik filters when especially bright aperture ratios of 1:2 or more come into play.

CCD filters from Astronomik highlight the contrast between objects. The SII filter highlights the contrast between ionized sulfur (SII) emission line objects and the skyglow background. Plus, this filter also completely obstructs artifical light sources such as mercury (Hg), sodium (Na), and skyglow, making it an excellent filter for use in heavily light polluted conditions. A superior quality substrate allows the Astronomik SII 6 nm CCD Filter to provide the same needle sharp star views you would see with your normal telescope.

Complete blockage of all unwanted wavelengths in the visible and IR bands of the spectrum is enabled by the Astronomik 27 mm SII 6 nm CCD Filter. As with all filters from Astronomik, this filter is parfocal with all other Astronomik filters. It is also diffraction limited so it won't compromise the optical performance of your telescope. Coatings keep this SII CCD filter from inducing scratches and other damaging effects from aging and high humidity. All Astronomik filters are delivered in a long-lasting plastic filter case of supreme quality.

Transmission Specifications

  • Typical 96% transmission in the SII (672 nm) line
  • Offers total blockage of unwanted light from UV up to IR