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Astronomik SII 12 nm CCD Filter - 1.25" - SII-1

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Astronomik SII 12 nm CCD Filter - 1.25" Round Mounted

  • This Astronomik SII CCD Filter is designed for astrophotography and comes mounted in a round 1.25" threaded cell
  • By designing the SII 12 nm CCD Filter with regards to peak technical standards, Astronomik has created a filter that provides the optical performance you seek for deep sky CCD imaging applications
  • Permits the light of ionized sulfur (SII) to be transmitted while obstructing close to the rest of the visual spectrum plus IR
  • Approximate FWHM bandwidth of 12 nm
  • Best-suited for imaging planetary nebulae and supernovae remnants
  • Made in Germany, a country renowned for their optical quality!

More About the Astronomik SII 12 nm CCD Filter - 1.25" Round Mounted

This 1.25" Round Mounted SII CCD Filter from Astronomik is the ultimate narrowband imaging filter for performing CCD astrophotography. Its 12 nm full width at half maximum (FWHM) is optimal for typical CCD cameras, allowing the use of exceptionally fast optics. The f/number application range spans from 1:2.8 to 1:15. Astronomik filters only experience transmission losses and chromatic distortions when severely bright aperture ratios of 1:2 or more are involved, whereas with other filters they arise with more frequency. A further benefit of 12 nm filters is the enhanced availability of guide stars for cameras featuring a built-in autoguider. Up to 99% transmission.

An excellent filter for dealing with heavy light pollution, the Astronomik SII 12 nm CCD Filter boosts contrast between objects in the SII emission line and the skyglow background while completely suppressing the emission lines of artificial mercury (Hg) and sodium (Na) light, as well as skyglow. With the Astronomik SII 12 nm CCD Filter, you'll observe razor sharp stars identical to those you're used to seeing with your regular telescope due to the supreme quality of the substrate.

Astronomik SII 12 nm CCD Filters offer total occlusion of unwanted wavelengths in the visible and IR parts of the spectrum. Parfocal with all other filters from Astronomik, this filter features an ultra thin substrate, and is diffraction-limited to maintain the optical efficiency of your telescope. Multi-layer coatings protect it from the impacts of scratching, aging, and high humidity. All Astronomik filters are delivered in a long-lasting plastic filter container of high quality.

Transmission Specifications

  • 97%+ transmission for the ionized sulfur (SII) line
  • Blocks almost the entire remainder of the visual spectrum
  • Blocks undesired infrared wavelengths