Astronomik CLS CCD Deep Sky & Light Pollution Filter T2

Product code: 8h00ed
Out of stock
Same as standard CLS but includes IR filter - choose if you use or plan to use a modded DSLR or CCD Camera
Out of stock. Please use our stock alert to be notified when ready.
You will earn 170 points with this purchase
Astronomik CLS CCD Deep Sky & Light Pollution Filter T2
This T2 mounted filter is 7.5mm thick and can be added into an imaging chain as if it was a simple 7.5mm T2 spacer!

The Astronomik CLS CCD 
light pollution filter
works on all objects for both visual use, and imaging with with CCD and plain glass (full spectrum) modded DSLR cameras. Blocks Sodium, Mercury and air-glow emission typically from street lighting. It is a great deep sky and general purpose filter. All the benefits of the CLS visual filter but with IR blocking built in.  For unmodified DSLR cameras choose the Standard CLS filter.

Main use

The filter blocks completely emission lines of artificial light sources like streetlights (e.g. sodium- and mercury-vapor) as well as the airglow. All 'important' emission lines as well as the spectral range of the night-adapted eye are beeing passed. The supplementary IR-blocking layer allows the use for DSLR- and Webcams without an integrated IR-block filter.

Other uses

  • Easier resolution of Double Stars.
  • With the EOS-Clip model, photography with DSLR cameras is feasible even unter extreme light-polluting conditions without shifting the white balance.
  • The 1,25" and 2" socket models can be used for observations from light-polluted areas.
  • If you plan to create color images from emission line data, our CLS-CCD filter is a great choice for the Luminance channel


CLS: For cameras with an integrated IR-filter or for visual observation.


  • Visual observation (dark skies): Good, to reduce light pollution by mercury-vapour lamps (streetlight)
  • Visual observation (urban skies): Reasonable, an UHC-E or UHC filter is more suitable
  • Film photography: Very good, colour balance is near perfect
  • CCD photography: Very good, optimized rejection of light pollution
  • DSLR photography (astro modified): Very good, colour balance is near perfect
  • DSLR photography (MC modified): Very good, colour balance is near perfect
  • DSLR photography (original): Very good, colour balance shifted but contrast enhanced
  • Webcam / Video (Planets): Unsuitable
  • Webcam / Video (Deep Sky): Very good, if light pollution is a big problem

Technical Data

  • 97% transmission at 656nm (H-alpha)
  • 95% transmission at 486nm (H-beta)
  • 95% transmission at 496nm (OIII)
  • 95% transmission at 501nm (OIII)
  • pass from 450 to 520nm and from 640 to 690nm
  • Parfocal with other Astronomik filters
  • Glass thickness: 1mm
  • Diffraction limited, the filter will not reduce the optical performance of your telescope!
  • Completely resistant against high humidity, scratches and aging effects
  • Astronomik filters are delivered in a high-quality, long lasting, filter box
Own this product? Let us know what you think.
Brand Astronomik
Condition New
Product Code 8h00ed