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Astronomik CLS Light Pollution Filter - T-Mount - CLS-T

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Astronomik CLS Light Pollution Filter - T-Mount

  • Gets rid of that irritating orange glare resulting from light pollution in heavily populated areas by obstructing mercury and sodium-vapor spectral lines while allowing the largest portion of visible light and H-alpha emissions to get through
  • Displays more detail of stars and nebulae
  • Functions best with telescopes featuring a filter to telescope aperture ratio of 1:3 to 1:15
  • Mounted in a round T-Mount cell
  • The Astronomik CLS Filter provides nearly 100% transmission between 450 nm and 530 nm which includes the visual and h-alpha portion of the spectrum
  • Multi-layer coatings on all Astronomik filters provide protection from scratches as well as the impacts of aging and high humidity
  • German-made for superior quality optics!

More About the Astronomik T-Mount CLS Filter:

For imaging deep sky objects like star clusters, nebulae, and galaxies in black & white as well as color with astronomical equipment of any size, the Astronomik CLS Filter is an excellent choice. Most surrounding light pollution is eliminated due to this filter's ability to simultaneously block mercury and sodium-vapor spectral lines while allowing visible light and H-alpha emissions to get through, thereby doing away with that annoying orange glow. Operates best with telescopes that have 1:3 to 1:15 filter to aperture ratios. Keeping within these aperture ratios removes aberrations and coma.

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

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