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Astronomik CLS Light Pollution Filter - Canon EOS Full Frame Clip


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  • Astronomik CLS Light Pollution Filter - Canon EOS Full Frame Clip:


    This is EOX XL Clip for Canon Full Frame cameras.

    • Compatible cameras:
    • - 5D Mk I (no live view)
    • - 5D Mk II
    • - 5D Mk III
    • - 6D Mk I
    • Non-compatible cameras:
    • - 5DS
    • - 5DSR
    • - 5D Mk IV
    • - 6D Mk II
    • - Canon APS-C (EF-S) cameras
    • - Canon Mirrorless cameras

    It is compatible with these cameras: EOS 6D, EOS 5D (no live view), EOS 5DMk II, and EOS 5D Mk III.

    Clip-in EOS XL filters are for these Canon Full-Format Cameras:  5D Mark II, 5D Mark III, and 6D.  (5D Mark I will work without LiveView only) 

    The Astronomik XL Clip filterswill not workwith: Canon 6D Mark II, 5DS, 5DSR, the 5D Mk IV camera bodies, and will only work without LiveView in the Canon 5D Mk I.

    A CLS Light Pollution Filter in a Full Frame XL Clip for Canon EOS cameras by Astronomik:

    The Astronomik CLS is a budget filter for visual observation, Black & White photography and CCD photographs of nebulae, galaxies and star clusters with astronomical instruments of any size.

    The Astronomik CLS blocks the light of the spectral lines of mercury and sodium-vapor lamps and lets the largest part of the visible light and H-alpha emissions pass. All the important emission lines, as well as the spectral region that the very well dark adapted eye can see, can pass through the filter.

    The filters are optimized for use with aperture ratios from 1:3 to 1:15. Transmission losses and chromatic distortions, which are problems with other filters, only appear with Astronomik filters when extremely bright aperture ratios of 1:2 and more are used. The CLS filter is suitable for use with telescopes of all aperture sizes and even works well with binoculars.

    The Astronomik CLS Light Pollution Filter is good for use under both dark and urban skies for reducing light pollution made by mercury-vapor lamps. For film photography and modified DSLR use, the CLS filter gives good performance and near perfect color balance. While this filter does perform well with webcam and video equipment under light polluted skies, it is not suitable for planetary use.



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


    About the Astronomik XL Clip-Filter System: The patented Astronomik Clip-Filter System for Canon full-frame cameras is black anodized aluminum and laser-cut on state-of-the-art modern machines. It can be inserted within seconds directly into any full-frame (5D and 6D, for example) EOS camera body. There are no changes necessary and all lens functions (focus, screen, image stabilization) remain functional! If you have a EOS Rebel, or other Canon APS-C sized camera body, you should purchase the standard-sized Astronomik CLS EOS Clip filter instead.

    [Exception: Does Not work with the Canon 5D Mark IV].

    Almost all Canon system lenses (with the exception of the EF-S series) and all M42 and T2 lens adapters, can be used with the Astronomik Clip-Filter System. The Clip-Filter System also acts as an outstanding dust shield, which prevents the possibility of dust settling on the sensor during long time exposure (The MC-Clear filter does not have a filter effect and only acts as a dust shield.)

    Astronomik CLS Light Pollution Filter - Canon EOS Clip Features:

    • 92-percent transmission at 486nm (H-beta)
    • 92-percent transmission at 496nm (OIII)
    • 92-percent transmission at 501nm (OIII)
    • 97-percent transmission at 656nm (H-alpha)
    • Pass from 450 to 540nm and beyond 650nm
    • Parfocal with other Astronomik filters
    • Glass thickness: 1mm
    • Completely resistant against high humidity, scratches and aging effects
    • Diffraction limited, the filter will not reduce the optical performance of your telescope!
    • Astronomik filters are delivered in a high-quality, long lasting, filter box


    OPT Product Number: AK-CLS-EOSXL


  • specifications

    Filter TypeLight Pollution/City Light Suppression
    Free ShippingYes
    Warranty10 Year Warranty

Product Reviews

Customer Reviews
4.3 Based on 7 Reviews
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    United States United States

    Effective, but difficult to install

    I've only had one chance to test this filter in my Canon 6D due to winter weather. Result was satisfactory, with blue color cast, same as the CLS in my APS-C camera. The filter itself is a bit difficult to install. You have to be very careful to seat both sides evenly in the lens well, taking care not to get fingerprints on it. Otherwise, neither camera cover nor lens can be installed properly. Also, the video supplied by Astronomik does not mention that you need to deactivate mirror lockup after installation of filter. The filter will support the mirror, and prevent it from falling back down. But, in Canon cameras, if you don't deactivate, after 30 secs the mirror will try to come down, creating vibration.

    United States United States

    Astronomic light polution filter

    Opt has always been a reliable source, and this time was no different.

    Jorge J.
    United States United States

    Not compatible

    Really didnt get to try it since it almost damage my Canon 6D Mark ii due to incompatibility issues

    United States

    A good recommendation

    This filter is easy to use, and suits my needs nicely. I’m not using it for astrophotography, but rather another project. I told one of your sales reps about the project, and he recommended this filter based on my description. I’m happy with the results.

    Steven B.
    United States

    Works as advertised

    Substantial improvement reducing light pollution in my Astro photos

    Andrew W.
    United States

    Fast ship and great service

    I ordered the filter on a Sunday. Much to my surprise, the shipment took place early Monday morning. Thanks OPT!