Optolong L-QEF 2" Quad Enhance Filter
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Vai al moduloOptolong Filter 2" L-QEF Quad Enhance
The Optolong L-QEF Quad Enhance 2" filter is designed for astrophotography under light-polluted skies. Featuring a quad-band transmission design, this filter effectively suppresses wavelengths generated by artificial light sources such as mercury and sodium lamps, significantly improving image contrast while maintaining a natural color balance.
Optimized for color cameras, the L-QEF is ideal for both wide-field imaging (such as the Milky Way) and deep-sky astrophotography targeting nebulae, star clusters, and galaxies. Its intelligent bandpass design reduces overall exposure time while preserving detail and color depth.
Advanced Optical Performance
The L-QEF filter delivers over 90% transmission on key nebula emission lines (H-Beta, OIII, H-Alpha, SII), enhancing the signal-to-noise ratio while reducing sky glow. With IR blocking up to 1000 nm, it minimizes infrared interference for improved clarity. Suitable for sky conditions from Bortle 1 to Bortle 7, it outperforms traditional broadband filters in light-polluted environments.
Main Features
- Suppresses light pollution from Hg/Na artificial light sources
- >90% transmission on H-Beta / OIII / H-Alpha / SII
- Improved signal-to-noise ratio (SNR)
- Near-infrared blocking up to 1000 nm
- Natural color balance and enhanced detail
- Compatible with color cameras
- Ideal for deep-sky and nebula imaging
Technical Specifications
| Substrate | Optical glass |
| Thickness | 1.85 mm |
| Type | Quad bandpass filter |
| Blocking range | 300–1000 nm |
| Blocking depth | OD2–OD4 |
| Surface quality | 60/40 |
| Transmitted wavefront RMS | λ/4 |
| Parallelism | 30″ |
The Optolong L-QEF Quad Enhance filter is an excellent choice for astrophotographers seeking superior contrast and detail under light-polluted skies while preserving accurate color representation.