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ZWO 1.25'' SII 7nm Narrowband Filter

ZWO 1.25" SII 7nm Narrowband Filter

£114.00✓ 2 year warranty


Usually shipped 7-10 working days.

About this product

Model:  zwo_sii_125-7nm
Part Number:  ZWO-SII7nm1.25

New & Improved with higher light transmission and less reflection (reduced halos around bright stars). 

The ZWO narrowband S-II filter passes light at 672nm wavelength with a bandpass of 7nm.

Use with H-alpha and OIII narrowband filters (SHO Set) for astrophotography. 

Also suitable for visual observation of most emission nebulae, planetary nebulae and supernova remnants. 


  • FWHM: 7 ±0.5nm
  • Glass Thickness 2.0+/-0.03 mm (1.25”/31mm/36mm)
  • Fine optically polished glass ensures accurate 1/4 wavefront over both surfaces
  • About 90% transmission at SII line 672nm
  • Infrared wavelength 700-1100nm cut-off
  • <0.1% transmission of off-band, OD3 (Optical Density)

Transmission Curve

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