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Astronomik CLS Light Pollution Filter - SC Rear Cell - CLS-SCT

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Astronomik CLS Light Pollution Filter - SC Rear Cell

  • Prevents that annoying orange glare caused by urban light pollution by blocking the spectral lines of mercury and sodium-vapor lamps while letting the biggest section of visible light and H-alpha emissions to pass
  • Shows additional star and nebula detail
  • Optimized for telescopes with a filter to telescope aperture ratio of 1:3 to 1:15
  • Round, mounted SC Rear Cell format
  • The Astronomik SCT Rear Cell CLS Filter enables nearly 100% transmission from 450 nm to 530 nm which includes the visual and H-alpha spectral area
  • Multi-layer coatings on all Astronomik filters prevent scratching and stave off the effects of aging and high humidity
  • German-made for exceptional optical quality!

More About the Astronomik SCT Rear Cell CLS Filter:

The Astronomik CLS filter is a great choice for black & white or color imaging of deep sky objects such as nebulae, galaxies, and star clusters with any sized astronomical instrument. Mercury and sodium-vapor spectral lines are blocked while the largest area of visible light and H-alpha emissions are allowed to pass. This enables the CLS filter to cut off the most of the surrounding light pollution, thereby eliminating that irritating orange glow. Optimized for use with 1:3 to 1:15 filter to aperture ratios. By staying within these parameters, aberrations and coma are eradicated.

As with all Astronomik filters, the SCT Rear Cell CLS Light Pollution Filter is parfocal with all other Astronomik filters. It has a thickness of only 1 mm and is highly resistant to scratches as well as the effects of aging and high humidity. Diffraction limited, this filter will not degrade your telescope's optical performance! Astronomik filters are shipped with a sturdy, high-quality 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