Optolong L-Synergy dual-narrow band filter FWHM7nm - 2" Mounted

A. About Optolong's L-Synergy Filter

Optolong L-Synergy‌ is a dual 7nm narrowband filter compatible with DSLR cameras, color CMOS sensors, and CCD cameras, supporting telescope systems with F-ratio of F3.3 or above (slower system）. Its key advantage lies in enabling astrophotography amateurs to capture exceptionally detailed emission nebulae even in light-polluted environments. it has been optimized to minimize bright star halos while isolating all emission lines except SII and OIII, achieving maximum effective transmission.

1. Optolong's L-Synergy

• O‌potlong L-Synergy‌ is a dual 7nm narrowband filter compatible with DSLR cameras, color CMOS sensors, and CCD cameras, supporting telescope systems with F-ratio of F3.3 or above (slower system）. Its key advantage lies in enabling astrophotography amateurs to capture exceptionally detailed emission nebulae even in light-polluted environments.

  After years of technical refinement, it has been optimized to minimize bright star halos while isolating all emission lines except SII and OIII, achieving maximum effective transmission.

Key Features:

• Optolong L-Synergy's advantage lies in its selective transmission of only the nebula emission lines OIII (500.7nm) and SII (672.4nm), while blocking all other light-polluting emission lines. This ensures that only the signals from oxygen and sulfur elements are captured during imaging, resulting in a darker sky background and significantly enhanced contrast and signal-to-noise ratio (SNR) between nebulae.

  Even in heavily light-polluted areas, this filter selectively transmits nebula emission lines while filtering out light pollution, ultimately eliminating its impact on astrophotography.

   

2. 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.

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.