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Light pollution filters

SVBONY CLS 1.25 in (FUSF9155A)

SVBONY's 1.25-inch CLS broadband filter: 90% transmission at the H-beta, OIII, H-alpha and SII nebula lines and 0.1% at the sodium and mercury lines of artificial lighting, with ion-assisted coatings.

SVBONY 1.25 inch CLS light pollution filter

SVBONY CLS 1.25 in (FUSF9155A)

SVBONY's 1.25-inch CLS broadband filter: 90% transmission at the H-beta, OIII, H-alpha and SII nebula lines and 0.1% at the sodium and mercury lines of artificial lighting, with ion-assisted coatings.

Blocked wavelengths and published curve
Off-band 0.1% at sodium 589 nm and mercury 435 and 578 nm · pass-band 90% at H-beta 486, OIII 496 and 500, H-alpha 656, SII 672 nm
LED and sodium behavior
Sodium and mercury lines blocked, stated · LED behavior not stated
Visual or photographic design
Broadband, stated suitable for color CCD cameras and unmodified DSLRs
Color cast
Not published by the maker.
Thread size
1.25 in
Focal ratio limits
Not published · central wavelength stated stable with temperature
Amazon reference
B079BWD595
EAN
0609378745577
  • Pass-band and off-band transmissions published at named lines
  • Ion-assisted deposition coating, stated durable
  • Little effect on white LED light pollution

Best for: Imaging or observing emission nebulae from a town, with a color camera or by eye

≈ $32
Check price on Amazon

Specifications

Blocked wavelengths and published curve
Off-band 0.1% at sodium 589 nm and mercury 435 and 578 nm · pass-band 90% at H-beta 486, OIII 496 and 500, H-alpha 656, SII 672 nm
LED and sodium behavior
Sodium and mercury lines blocked, stated · LED behavior not stated
Visual or photographic design
Broadband, stated suitable for color CCD cameras and unmodified DSLRs
Color cast
Not published by the maker.
Thread size
1.25 in
Focal ratio limits
Not published · central wavelength stated stable with temperature
Amazon reference
B079BWD595
EAN
0609378745577

Published lines

SVBONY publishes what the filter passes and blocks, line by line: 90% transmission at H-beta 486 nm, OIII 496 and 500 nm, H-alpha 656 nm and SII 672 nm; 0.1% at sodium 589 nm and mercury 435 and 578 nm. Few filters at this price give that much.

Coatings

Ion-assisted deposition for durability and scratch resistance, with a central wavelength stated stable as temperature changes, and a planetary rotation system for even coating.

For color cameras

SVBONY says it suits color CCD cameras and unmodified DSLRs, where it cuts the orange glow of sodium lighting from images of emission nebulae.

The LED caveat

White LED streetlights emit across the spectrum. A CLS filter blocks little of that light.

Price and availability

On November 7, 2026, Amazon.com listed it at about $32 from a third-party seller.

Figures as Keepa reported them on the day this page was last updated. Stock and pricing shift without warning.

Prices quoted in this text were read on November 7, 2026. The live price is at the top of the page.

What gets asked before buying

What does CLS mean?

City Light Suppression: a broadband filter that blocks the strongest lines of sodium and mercury lighting while passing nebula emission lines.

Visual or photographic?

Both. SVBONY pitches it for color cameras and unmodified DSLRs; visually it darkens a sky lit by sodium lamps.

How does it differ from a UHC?

A UHC is narrower around H-beta and OIII and gives more visual contrast on nebulae; a CLS passes more of the spectrum, including H-alpha and SII, which suits color imaging. Compare with the [SVBONY UHC](/reviews/nebula-filters-svbony/).

What barrel it suits

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    Blocked wavelengths and published curve
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    EAN
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