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Astronomik SII 6 nm CCD Filter - 42 mm Round - SII6-42

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Astronomik SII 6 nm CCD Filter - 42 mm Round

  • Astronomik's SII 6 nm CCD Filter has been created for the express purpose of CCD astrophotography with this particular filter presented in a round 42 mm format
  • Designed with regards to peak technical standards for the superb optical perfomance needed for deep sky astrophotography
  • Transmits ionized sulfur (SII) light while cutting off the full remainder of the visible spectrum plus IR at the same time
  • Approximate FWHM bandwidth of 6 nm
  • Ideally equipped for imaging deep sky objects such as planetary nebulae and the remnants of supernovae
  • Made in Germany, a country with a reputation for producing optics of supreme quality!

More About Astronomik SII 6 nm CCD Filters

This 42 mm SII 6 nm CCD Filter from Astronomik is the perfect narrowband filter for CCD astro-imaging. With a smaller FWHM (full width at half maximum) of 6 nm, coupled with a usual 96% transmission, this filter is able to provide a remarkable contrast boost. All undesired wavelengths of light not in the SII line (672 nm) are completely occluded from UV up to the IR. This results in a background that is exceptionally dark. With Astronomik filters, transmission reductions and chromatic aberrations only crop up when extremely bright aperture ratios of 1:2 and above are involved, contrary to filters made by other manufacturers.

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 42 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 storage case of supreme quality.

Transmission Specifications

  • For the SII (672 nm) line, typical transmission is 96%
  • Provides complete obstruction of unwanted light from UV up to IR