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Astronomik SII 12 nm CCD Filter - T-Mount - SII-T

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Astronomik SII 12 nm CCD Filter - T-Mount

  • Mounted in a round, t-threaded cell, the Astronomik SII CCD Filter is made for astrophotography
  • 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
  • Close to 12 nm FWHM bandwidth
  • Optimally suited for imaging planetary nebulae and supernova remnants
  • German-made for high optical quality!

More About the Astronomik T-Thread Mounted SII 12 nm CCD Filter

This SII CCD T-Mount Filter from Astronomik is the ultimate narrowband imaging filter. For common CCD cameras, this filter's 12 nm full width at half maximum (FWHM) is ideal as it allows extremely fast optics to be employed. The f/number application range is between 1:2.8 and 1:15. Astronomik filters only experience transmission losses and chromatic distortions when severely bright aperture ratios of 1:2 or more are involved, whereas they arise much more frequently with other filters. An additonal advantage of 12 nm filters is the enhanced guide star availability for cameras with an integrated autoguider. The Astronomik SII 12 nm CCD Filter has a transmission of up to 99%.

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.

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

  • More than 97% transmission of the SII ionized sulfur line
  • Offers nearly complete occlusion of the rest of visual spectrum
  • Cuts off undesired wavelengths in the infrared