Optolong

Optolong CLS-CCD Light Pollution Filter


  • Sale
  • Regular price $96.00

Available to Order, usually 7-10 days to ship.


  • CLS-CCD is different from CLS with infrared wavelength 700-1100nm cut-off
  • Fits color CCD cameras and modified DSLRs for astrophotography
  • Works well on most emission nebulae, planetary nebulae, and supernova remnants
  • Noticeable boost in contrast and visibility of the fainter outer detail

The CLS-CCD broadband filter is designed to improve the visibility of various deep sky objects by selectively reducing the transmission of wavelengths of light pollutants.  Specifically, it reduces those produced by artificial lighting, including mercury vapor lamps, both high & low pressure sodium vapor lights, and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).

The CLS-CCD filter is highly transparent in main nebula emission lines at OIII (496nm and 500nm), H-beta (486nm), NII (654nm and 658nm), H-alpha (656nm) as well as SII (672nm).  It enhances the contrast and details for both visual and photographic purposes in non-rural areas.

Main Use and Performance

  • The CLS-CCD filter is different from the CLS filter, with an infrared wavelength 700-1100nm cut-off
  • Fits color CCD cameras and modified DSLRs for astrophotography
  • Work well on most emission nebulae, planetary nebulae, and supernova remnants
  • Noticeable boost in contrast and visibility of the fainter outer detail
  • Light pollution filters do not eliminate the effects of light pollution or increase the object’s brightness. In many cases, they increase the contrast between nebula and night sky, without brightening the nebula.

    Technical Data

    • Schott substrate material
    • Thickness 2.0mm (1.25”/2”/36mm)
    • Thickenss 1.0mm (clip series)
    • Surface Quality: 60/40 (Refer to MIL-O-13830)
    • Optically polished to ensure accurate 1/4 wavefront and <30 seconds parallelism over both surfaces
    • 95% transmission of the main nebula emission lines (i.e. H-alpha 656nm, OIII 496nm and 500nm, SII 672nm and H-beta 486nm)
    • 0.1% transmission of off-band, specifically the major emission lines of artificial light pollution (i.e. Na 589nm, Hg 435nm and 578nm).  Transmission of 0.1% is equivalent to OD3 (Optical Density), where a high optical density value indicates very low transmission, and low optical density indicates high transmission.

    Coating Parameter

    • Non-cemented optical substrate coating
    • Electron-beam gun evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL (central wavelength); no deviation affected by temperature change
    • Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band


    Filter Cell

    • Ultra-thin filter cell minimizes vignetting by maximizing possible clear aperture (clear aperture is 26mm for 1.25”; 45mm for 2”)
    • Aerometal Material
    • Precise CNC Machining
    • Sand Blasting Process
    • Black Anodized Finish
    • Extinction Treatment to Prevent Reflection
    • Laser Engraving No Fading

    Package

    • Plastic PP Case
    • Imported High Pressure EVA Case Lining
    • Silver Cardboard Box
    • High Density Sponge Carton Lining

    Sizes

    • Standard 1.25”
    • Standard 2”
    • Clip filter for Canon EOS crop sensor 
    SKU: 11901
    Barcode: