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ZWO Narrowband 7nm 31mm Filter Set
The ZWO Narrowband 7nm 31mm Filter Set includes H-alpha, O-III, and S-II filters, isolating key wavelengths for enhanced contrast and detail in deep-sky nebula astrophotography.
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The ZWO 7nm Narrowband Filter Set (31mm) combines H-alpha, S-III and O-III filters. This narrowband filter set's purpose is for observing nebulae, in particular. These filters should increase the contrast and are not used to increase the target's brightness or reduce the amount of light pollution.
Technical Parameter:
Size: D=31mm
Thickness: 2mm
Technical Data
- FWHM：7±0.5nm
- Glass Thickness 2.0+/-0.03 mm (1.25”/31mm/36mm)
- Optics are polished in order to achieve 1/4 wavefront
- Allows 90% transmission - H-alpha line 656nm (H-Alpha filter )
- About 90% transmission - SII line 672nm (SII filter )
- About 90% transmission - OIII line 500nm (OIII filter )
- Infrared wavelength at 700-1100nm cut-off
- <0.1% transmission of off-band, OD3(Optical Density)
About ZWO Optical: Astrophotography has never been easier
Established in 2011, ZWO Optical is a fast-growing global astroimaging camera powerhouse based in Suzhou China. They focus on building and innovating groundbreaking CMOS cameras such as the iconic ZWO ASI120MM Monochrome CMOS camera (the first-ever planetary CMOS camera to beat a CCD in the early 2010s). ZWO continues to pioneer new astrophotography technology with revolutionary features to capture exceptional quality of images of space that will last you a lifetime.
Today, ZWO cameras are recognised by every passionate astrophotographer and are available in over 25 countries internationally.
Product code: NB7nmD31