ZWO 1.25-inch H-alpha SII OIII 7nm Filter Set

  • The ZWO 1.25-inch H-alpha Sii Oiii 7nm Filter Set allows only ionized Hydrogen, Oxygen, and Sulfur emissions to be photographed.
  • These filter will enhance contrast for these elements wavelengths and block most wavelengths produced by city lights.
  • Glass thickness: 1.25 inches.
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  • Regular price $369.00

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ZWO 1.25-inch H-alpha SII OIII 7nm Filter Set

The ZWO 1.25-inch H alpha, Sii, Oiii, 7nm Filter Set will reduce the transmission of most wavelengths and only allow certain narrow bands to pass. 

Technical Specifications of the ZWO 1.25-inch Filter Set

  • FWHM: 7 plus or minus 0.5nm.
  • Glass Thickness 1.9+/-0.03 mm (1.25 inches/ 31 mm/ 36 mm).
  • Fine-optically polished to ensure accurate 1/4 wavefront over both surfaces.
  • About 90% transmission at H-alpha line 656nm (H-Alpha filter).
  • About 90% transmission at Sii line 672nm (Sii filter).
  • About 90% transmission at major Oiii line 500 nm (Oiii filter).


Filter Thickness1.9 mm
Filter TypeH Alpha
Filter TypeOIII
Filter TypeSII
Free ShippingYes


  • H-Alpha filter.
  • Sii Filter.
  • Oiii Filter.
  • Case.