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ZWO S II 36mm Unmounted Narrowband Filter
The ZWO SII 36mm Narrowband Filter isolates 672nm sulfur-II emissions with a 7nm bandwidth, enhancing contrast and detail in nebula imaging while reducing light pollution for astrophotography.
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The ZWO SII 36mm Narrowband Filter is designed for astrophotography, specialising in isolating the SII emission line at a 672nm wavelength. With a 7nm bandpass, this unmounted filter allows 80% light transmission, making it well-suited for capturing the fine details of deep-sky objects like nebulae. The filter is ideal for telescopes with focal ratios of f/5 or higher.
Constructed with optically polished glass, the filter ensures precise 1/4 wavefront performance on both surfaces, maintaining sharp image quality. It effectively reduces unwanted light from artificial sources such as mercury and sodium vapour, as well as natural skyglow. This makes it an excellent choice for astrophotographers working in light-polluted areas.
The ZWO SII 7nm filter can be used individually or in combination with H-alpha and OIII filters for tri-colour CCD imaging. It is also compatible with false-colour imaging setups, enhancing versatility for deep-sky imaging projects.
Technical Parameters:
- Size: D=36mm
- Thickness: 2mm
- Wavelength at 672nm with a bandpass of 7nm.
About ZWO Optical
Established in 2011, ZWO Optical is a fast-growing global astroimaging camera powerhouse based in Suzhou, China. Known for its iconic ZWO ASI 120MM Monochrome CMOS Camera, the first-ever planetary CMOS camera to beat a CCD in the early 2010s, ZWO has pioneered new astroimaging technology with revolutionary new features, including USB 3,0, cooled systems, ADC and more. Today, ZWO Cameras is known by every passionate astrophotographer and is available in over 25 countries world-wide.
Product code: SII7nmD36