Optolong L-Synergy Dual Band SII & OIII 7nm Filter - 2" Mounted
Stock count is accurate & shown in real time.
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
Contiguous US / Lower 48:
Free shipping applies to orders over $50 using our chosen carrier/method. Faster paid options are available at checkout.
Alaska, Hawaii & US Territories:
Free shipping applies to many—but not all—products. Enter your ZIP code in cart or upon checkout to confirm options and costs.
International:
International orders do not qualify for free shipping. Shipping, duties, brokerage, tariffs, and taxes are the customer’s responsibility. Some items may be restricted due to export, size, or manufacturer limitations.
-
Isolates two critical emission lines OIII (500.7 nm), and SII (672.4 nm) each with a narrow 7 nm bandwidth
-
Offers transmission rates greater than 85% for both wavelengths
-
Effectively blocks unwanted wavelengths outside the OIII and SII bands.
-
Designed for use with one-shot color (OSC) cameras, it simplifies the imaging process by enabling the capture of both emission lines in a single exposure.
-
Built with a 2" mounted design (M48x0.75 thread), it's compatible with a wide range of telescopes and imaging setups.
Optolong L-Synergy: Double the Bands, Double the Brilliance!
Introducing the Optolong L-Synergy Dual Band Filter! This 2" mounted filter is built with dual-narrowband technology designed especially for color camera users, making it easier to capture rich narrowband data without the need for multiple filters. By isolating the OIII (500.7 nm) and SII (672.4 nm) emission lines with a narrow 7 nm bandwidth, it passes the key signals while blocking unwanted light pollution. Perfect for imaging emission nebulae, planetary nebulae, and other colorful deep-sky objects, it delivers stunning results even under bright city skies.
A transmission chart, like the one above, is a filter’s fingerprint! It shows which colors of light the filter lets through (the tall peaks) and which it blocks out (the flat areas), helping you see how it boosts nebula signals while cutting light pollution.
Explore how the L-Synergy helps one-shot color astrophotographers capture narrowband detail in emission nebulae in our new video below!
The L-Synergy in Action!
Gear:
- Telescope: Tecnosky Carbon 200
- Camera: ZWO ASI 2600 duo
- Mount: ZWO AM5
- Filter: Optolong L-Synergy
200 × 5-minute exposures
Gear:
- Telescope: TS 90 OWL
- Camera: Omegon 571vTec
- Mount: EQ6 mod Rowan
- Filter: Optolong L-Synergy
52 × 10-minute subs
Traditional Narrowband for OSC
The innovation of the L-Synergy filter lies in its precise combination of dual-narrowband technology designed for color camera users. By isolating SII and OIII, it fills the gap that traditional Ha + OIII filters leave behind, giving one-shot color imagers access to the missing SHO component. This makes it possible to create Hubble Palette-style deep-sky images comparable to those captured with monochrome SHO systems—without switching cameras or investing in multiple filters. The result is professional-level narrowband imaging made more accessible and affordable.
Emission Line Isolation
The L-Synergy filter selectively transmits only the nebula emission lines OIII (500.7 nm) and SII (672.4 nm) while blocking all other light-polluting wavelengths. This ensures that oxygen and sulfur signals are captured cleanly, producing a darker sky background and significantly enhancing contrast and signal-to-noise ratio (SNR). Even in heavily light-polluted areas, it effectively isolates nebula emission lines, minimizing the impact of unwanted light and delivering clearer, more detailed astrophotography.
Compatability
This filter is a dual 7 nm narrowband filter compatible with DSLR/CCD cameras, and color CMOS sensors! Supporting telescope systems with ratios of f/3.3 or above (slower systems). Its key advantage lies in enabling astrophotography amateurs to capture exceptionally detailed emission nebulae even in light-polluted environments. This filter comes in a standard 2" mounted design with M48x0.75 threads, making it easy to screw into most filter wheels, focusers, and accessories. Its versatile threading ensures broad compatibility across a wide range of telescope setups!
Optical Design
By analyzing the spectral characteristics of both celestial emission lines and light pollution, L-Synergy selectively preserves the SII and OIII nebula colors while filtering out the majority of light pollution. Specifically designed and optically optimized, L-Synergy maintains consistently high transmission across both SII and OIII bands. This ensures users can precisely capture the target nebula emissions, delivering optimal astrophotography results.
Specifications
- Filter Size: 2" (M48×0.75) threaded mount
- Emission Lines: Isolates SII (672.4 nm) and OIII (500.7 nm)
- Transmission: Greater than 85% for both SII and OIII
- Bandwidth: Each line has a 7 nm Full Width at Half Maximum (FWHM)
- Thickness: 1.85 mm
- Focal Ratio Compatibility: Designed for telescopes with a focal ratio of f/3.3 or higher
- Substrate: Multi-Coated Optical glass
Useful Resources
Filter Cell Specifications
D = Filter Cell Diameter = 50.3 mm / 2.0 in
T = Total Filter Height = 6.8 mm / 0.26 in
C = Filter Cell Height (Excluding Male Thread) = 4.8 mm / 0.18 in
M = Male Thread Length = 2.0 mm / 0.07 in
F = USABLE Female Filter Thread Length = Not threaded, so you cannot stack additional filters
S = Glass Substrate Thickness = 2 mm / 0.07 in
CA = Clear Aperture = 44 mm / 1.73 in
Other Information
- Country of Manufacture: China
Optolong L-Synergy: Double the Bands, Double the Brilliance!
Introducing the Optolong L-Synergy Dual Band Filter! This 2" mounted filter is built with dual-narrowband technology designed especially for color camera users, making it easier to capture rich narrowband data without the need for multiple filters. By isolating the OIII (500.7 nm) and SII (672.4 nm) emission lines with a narrow 7 nm bandwidth, it passes the key signals while blocking unwanted light pollution. Perfect for imaging emission nebulae, planetary nebulae, and other colorful deep-sky objects, it delivers stunning results even under bright city skies.
A transmission chart, like the one above, is a filter’s fingerprint! It shows which colors of light the filter lets through (the tall peaks) and which it blocks out (the flat areas), helping you see how it boosts nebula signals while cutting light pollution.
Explore how the L-Synergy helps one-shot color astrophotographers capture narrowband detail in emission nebulae in our new video below!
The L-Synergy in Action!
Gear:
- Telescope: Tecnosky Carbon 200
- Camera: ZWO ASI 2600 duo
- Mount: ZWO AM5
- Filter: Optolong L-Synergy
200 × 5-minute exposures
Gear:
- Telescope: TS 90 OWL
- Camera: Omegon 571vTec
- Mount: EQ6 mod Rowan
- Filter: Optolong L-Synergy
52 × 10-minute subs
Traditional Narrowband for OSC
The innovation of the L-Synergy filter lies in its precise combination of dual-narrowband technology designed for color camera users. By isolating SII and OIII, it fills the gap that traditional Ha + OIII filters leave behind, giving one-shot color imagers access to the missing SHO component. This makes it possible to create Hubble Palette-style deep-sky images comparable to those captured with monochrome SHO systems—without switching cameras or investing in multiple filters. The result is professional-level narrowband imaging made more accessible and affordable.
Emission Line Isolation
The L-Synergy filter selectively transmits only the nebula emission lines OIII (500.7 nm) and SII (672.4 nm) while blocking all other light-polluting wavelengths. This ensures that oxygen and sulfur signals are captured cleanly, producing a darker sky background and significantly enhancing contrast and signal-to-noise ratio (SNR). Even in heavily light-polluted areas, it effectively isolates nebula emission lines, minimizing the impact of unwanted light and delivering clearer, more detailed astrophotography.
Compatability
This filter is a dual 7 nm narrowband filter compatible with DSLR/CCD cameras, and color CMOS sensors! Supporting telescope systems with ratios of f/3.3 or above (slower systems). Its key advantage lies in enabling astrophotography amateurs to capture exceptionally detailed emission nebulae even in light-polluted environments. This filter comes in a standard 2" mounted design with M48x0.75 threads, making it easy to screw into most filter wheels, focusers, and accessories. Its versatile threading ensures broad compatibility across a wide range of telescope setups!
Optical Design
By analyzing the spectral characteristics of both celestial emission lines and light pollution, L-Synergy selectively preserves the SII and OIII nebula colors while filtering out the majority of light pollution. Specifically designed and optically optimized, L-Synergy maintains consistently high transmission across both SII and OIII bands. This ensures users can precisely capture the target nebula emissions, delivering optimal astrophotography results.
Specifications
- Filter Size: 2" (M48×0.75) threaded mount
- Emission Lines: Isolates SII (672.4 nm) and OIII (500.7 nm)
- Transmission: Greater than 85% for both SII and OIII
- Bandwidth: Each line has a 7 nm Full Width at Half Maximum (FWHM)
- Thickness: 1.85 mm
- Focal Ratio Compatibility: Designed for telescopes with a focal ratio of f/3.3 or higher
- Substrate: Multi-Coated Optical glass
- 1x L-Synergy Dual Band Filter
- Dust Case
-
Isolates two critical emission lines OIII (500.7 nm), and SII (672.4 nm) each with a narrow 7 nm bandwidth
-
Offers transmission rates greater than 85% for both wavelengths
-
Effectively blocks unwanted wavelengths outside the OIII and SII bands.
-
Designed for use with one-shot color (OSC) cameras, it simplifies the imaging process by enabling the capture of both emission lines in a single exposure.
-
Built with a 2" mounted design (M48x0.75 thread), it's compatible with a wide range of telescopes and imaging setups.
Optolong L-Synergy: Double the Bands, Double the Brilliance!
Introducing the Optolong L-Synergy Dual Band Filter! This 2" mounted filter is built with dual-narrowband technology designed especially for color camera users, making it easier to capture rich narrowband data without the need for multiple filters. By isolating the OIII (500.7 nm) and SII (672.4 nm) emission lines with a narrow 7 nm bandwidth, it passes the key signals while blocking unwanted light pollution. Perfect for imaging emission nebulae, planetary nebulae, and other colorful deep-sky objects, it delivers stunning results even under bright city skies.
A transmission chart, like the one above, is a filter’s fingerprint! It shows which colors of light the filter lets through (the tall peaks) and which it blocks out (the flat areas), helping you see how it boosts nebula signals while cutting light pollution.
Explore how the L-Synergy helps one-shot color astrophotographers capture narrowband detail in emission nebulae in our new video below!
The L-Synergy in Action!
Gear:
- Telescope: Tecnosky Carbon 200
- Camera: ZWO ASI 2600 duo
- Mount: ZWO AM5
- Filter: Optolong L-Synergy
200 × 5-minute exposures
Gear:
- Telescope: TS 90 OWL
- Camera: Omegon 571vTec
- Mount: EQ6 mod Rowan
- Filter: Optolong L-Synergy
52 × 10-minute subs
Traditional Narrowband for OSC
The innovation of the L-Synergy filter lies in its precise combination of dual-narrowband technology designed for color camera users. By isolating SII and OIII, it fills the gap that traditional Ha + OIII filters leave behind, giving one-shot color imagers access to the missing SHO component. This makes it possible to create Hubble Palette-style deep-sky images comparable to those captured with monochrome SHO systems—without switching cameras or investing in multiple filters. The result is professional-level narrowband imaging made more accessible and affordable.
Emission Line Isolation
The L-Synergy filter selectively transmits only the nebula emission lines OIII (500.7 nm) and SII (672.4 nm) while blocking all other light-polluting wavelengths. This ensures that oxygen and sulfur signals are captured cleanly, producing a darker sky background and significantly enhancing contrast and signal-to-noise ratio (SNR). Even in heavily light-polluted areas, it effectively isolates nebula emission lines, minimizing the impact of unwanted light and delivering clearer, more detailed astrophotography.
Compatability
This filter is a dual 7 nm narrowband filter compatible with DSLR/CCD cameras, and color CMOS sensors! Supporting telescope systems with ratios of f/3.3 or above (slower systems). Its key advantage lies in enabling astrophotography amateurs to capture exceptionally detailed emission nebulae even in light-polluted environments. This filter comes in a standard 2" mounted design with M48x0.75 threads, making it easy to screw into most filter wheels, focusers, and accessories. Its versatile threading ensures broad compatibility across a wide range of telescope setups!
Optical Design
By analyzing the spectral characteristics of both celestial emission lines and light pollution, L-Synergy selectively preserves the SII and OIII nebula colors while filtering out the majority of light pollution. Specifically designed and optically optimized, L-Synergy maintains consistently high transmission across both SII and OIII bands. This ensures users can precisely capture the target nebula emissions, delivering optimal astrophotography results.
Specifications
- Filter Size: 2" (M48×0.75) threaded mount
- Emission Lines: Isolates SII (672.4 nm) and OIII (500.7 nm)
- Transmission: Greater than 85% for both SII and OIII
- Bandwidth: Each line has a 7 nm Full Width at Half Maximum (FWHM)
- Thickness: 1.85 mm
- Focal Ratio Compatibility: Designed for telescopes with a focal ratio of f/3.3 or higher
- Substrate: Multi-Coated Optical glass
Useful Resources
Filter Cell Specifications
D = Filter Cell Diameter = 50.3 mm / 2.0 in
T = Total Filter Height = 6.8 mm / 0.26 in
C = Filter Cell Height (Excluding Male Thread) = 4.8 mm / 0.18 in
M = Male Thread Length = 2.0 mm / 0.07 in
F = USABLE Female Filter Thread Length = Not threaded, so you cannot stack additional filters
S = Glass Substrate Thickness = 2 mm / 0.07 in
CA = Clear Aperture = 44 mm / 1.73 in
Other Information
- Country of Manufacture: China
- 1x L-Synergy Dual Band Filter
- Dust Case
Optolong L-Synergy Dual Band SII & OIII 7nm Filter - 2" Mounted