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.
  • Sale
  • Regular price $399.00
  • $369.00
  • You save: $30.00 (7%)

In Stock
Free Shipping
Add to Wishlist
Already have gear? Trade it in for cash or new equipment.

Accessories Added

Rod, Telescope Expert

Want Help?

Just ask one of our sales reps


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.