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Astronomik CLS Light Pollution Filter - 31 mm Round - CLS-31

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SKU: ASF-CLS-31
 

Astronomik 31 mm CLS Light Pollution Filter


  • Blocks the light of the spectral lines of mercury and sodium-vapor lamps and lets the largest part of visible light and H-alpha emissions pass, thereby eliminating most of the orange glow caused by urban light pollution
  • Shows more stars and nebula detail
  • Optimized for telescopes that have a 1:3 to 1:15 filter to telescope aperture ratio
  • This Astronomik CLS Light Pollution Filter is constructed in a 31 mm round format
  • Offers almost 100% transmission between 450 nm and 530 nm which includes the visual and h-alpha area of the spectrum
  • All Astronomik filters feature multi-layer coatings for superior protection against scratching, aging and humidity
  • Made in Germany, a country known for producing high-quality optics!


More About the Astronomik 31 mm CLS Filter:


For imaging deep sky objects like star clusters, nebulae and galaxies in both black & white and color with astronomical instruments of all sizes, the Astronomik CLS Filter is an excellent choice. By impeding the spectral lines of mercury and sodium-vapor lamps, and allowing the biggest section of the visible light and H-alpha emissions to pass, this filter will obstruct most of the encompassing light pollution, eliminating that bothersome orange glow. Developed for use with filter to aperture ratios between 1:3 and 1:15. Aberrations and coma can be eliminated by staying within these parameters.

All Astronomik filters are parfocal with all other Astronomik filters. The Astronomik 31 mm CLS Light Pollution Filter is only 1 mm thick. It is highly resistant to scratches and aging impressions, as well as high humidity. Diffraction limited, this filter will not lessen the optical efficiency of your telescope! Astronomik filters arrive in a superior quality, long-lasting plastic storage box.

Transmission Specifications:


  • 92% transmission at 486 nm (H-beta)
  • 92% transmission at 496 nm (OIII)
  • 92% transmission at 501 nm (OIII)
  • 97% transmission at 656 nm (H alpha)
  • Pass from 450 to 540 nm and beyond 650 nm