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Astronomik SII 12 nm CCD Filter - SCT Rear Cell - SII-SCT

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SKU: ASF-SII-SCT

Astronomik SII 12 nm CCD Filter - SCT Rear Cell


  • Astronomik SII CCD Filters are made for CCD photography with this particular model mounted in an SCT rear cell format
  • Created with the highest technical standards in mind to offer the optical efficiency needed to perform deep sky imaging operations with your CCD camera
  • Permits the light of ionized sulfur (SII) to be transmitted while obstructing close to the rest of the visual spectrum plus IR
  • Nearly 12 nm FWHM bandwidth
  • Ideal for imaging planetary nebulae and supernova remnants
  • German-made for superior optical quality!


More About the Astronomik SII 12 nm CCD SCT Filter


For performing CCD photography tasks, this SC Rear Cell mounted SII CCD narrowband filter from Astronomik is ideal. With an FWHM (full width at half maximum) of 12 nm, the Astronomik SII CCD is optimal for common CCD cameras, allowing the use of exceptionally fast optics. The focal ratio application range stretches from 1:2.8 to 1:15. Transmission losses and chromatic aberrations only transpire with Astronomik filters when excessively bright 1:2 or more aperture ratios are used, unlike other filters. It should be acknowledged that this filter features a transmission of up to 99%. Another benefit of 12 nm filters is the high availability of guiding stars for cameras that incorporate an autoguider.

Astronomik's CCD filters enhance the contrast between objects. The SII filter enhances contrast between SII emission line objects and the background sky while offering total suppression of mercury (Hg) and sodium (Na) and other artificial light emissions, as well as skyglow, making it an excellent filter to use in light polluted conditions. Because of the high quality of the Astronomik SII 12 nm CCD substrate, you'll see the same razor sharp stars as you would from your regular telescope.

All unwanted visible and IR spectral band wavelengths are fully obstructed with this SCT mounted SII 12 nm CCD Filter from Astronomik. Like all Astronomik filters, the SC Rear Cell SII 12 nm CCD Filter is parfocal with all other Astronomik filters. It has an ultra thin substrate and is diffraction limited to preserve your telescope's optical performance. Coatings offer total protection from scratching as well as the effects of aging and high humidity. All Astronomik filters arrive in a long-lasting, supreme quality plastic filter container.

Transmission Specifications


  • More than 97% transmission of the ionized sulfur (SII) line
  • Blocks close to the whole remainder of the visual spectrum
  • Blocks undesired wavelengths in the infrared