{"product_id":"optolong-l-qef-2-quad-enhance-filtro-astrofotografia","title":"Optolong L-QEF 2\" Quad Enhance Filter","description":"\u003ch2\u003eOptolong Filter 2\" L-QEF Quad Enhance\u003c\/h2\u003e\n\u003cp\u003eThe Optolong L-QEF Quad Enhance 2\" filter is designed for astrophotography under light-polluted skies. Featuring a \u003cstrong\u003equad-band transmission design\u003c\/strong\u003e, 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.\u003c\/p\u003e\n\n\u003cp\u003eOptimized for color cameras, the L-QEF is ideal for both \u003cstrong\u003ewide-field imaging\u003c\/strong\u003e (such as the Milky Way) and \u003cstrong\u003edeep-sky astrophotography\u003c\/strong\u003e targeting nebulae, star clusters, and galaxies. Its intelligent bandpass design reduces overall exposure time while preserving detail and color depth.\u003c\/p\u003e\n\n\u003ch3\u003eAdvanced Optical Performance\u003c\/h3\u003e\n\u003cp\u003eThe L-QEF filter delivers \u003cstrong\u003eover 90% transmission\u003c\/strong\u003e on key nebula emission lines (H-Beta, OIII, H-Alpha, SII), enhancing the signal-to-noise ratio while reducing sky glow. With \u003cstrong\u003eIR blocking up to 1000 nm\u003c\/strong\u003e, it minimizes infrared interference for improved clarity. Suitable for sky conditions from \u003cstrong\u003eBortle 1 to Bortle 7\u003c\/strong\u003e, it outperforms traditional broadband filters in light-polluted environments.\u003c\/p\u003e\n\n\u003ch3\u003eMain Features\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eSuppresses light pollution from Hg\/Na artificial light sources\u003c\/li\u003e\n  \u003cli\u003e\u003e90% transmission on H-Beta \/ OIII \/ H-Alpha \/ SII\u003c\/li\u003e\n  \u003cli\u003eImproved signal-to-noise ratio (SNR)\u003c\/li\u003e\n  \u003cli\u003eNear-infrared blocking up to 1000 nm\u003c\/li\u003e\n  \u003cli\u003eNatural color balance and enhanced detail\u003c\/li\u003e\n  \u003cli\u003eCompatible with color cameras\u003c\/li\u003e\n  \u003cli\u003eIdeal for deep-sky and nebula imaging\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\u003ctd\u003eSubstrate\u003c\/td\u003e\u003ctd\u003eOptical glass\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eThickness\u003c\/td\u003e\u003ctd\u003e1.85 mm\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eType\u003c\/td\u003e\u003ctd\u003eQuad bandpass filter\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eBlocking range\u003c\/td\u003e\u003ctd\u003e300–1000 nm\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eBlocking depth\u003c\/td\u003e\u003ctd\u003eOD2–OD4\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eSurface quality\u003c\/td\u003e\u003ctd\u003e60\/40\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eTransmitted wavefront RMS\u003c\/td\u003e\u003ctd\u003eλ\/4\u003c\/td\u003e\u003c\/tr\u003e\n    \u003ctr\u003e\u003ctd\u003eParallelism\u003c\/td\u003e\u003ctd\u003e30″\u003c\/td\u003e\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cp\u003eThe 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.\u003c\/p\u003e","brand":"Optolong","offers":[{"title":"Default Title","offer_id":51260816654667,"sku":"OPL-QEF-2","price":219.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0886\/1981\/1147\/files\/optolong_filtro_2_pollici_L-QEF_quad_enhance_astrografia_riduzione_inquinamento_luminoso.jpg?v=1756457994","url":"https:\/\/adriasky.it\/en\/products\/optolong-l-qef-2-quad-enhance-filter","provider":"Adriasky","version":"1.0","type":"link"}