ZWO Ha 7nm filter 2in increases the contrast between nebula and night sky by helping to reduce the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapour, and both high and low pressure sodium vapour lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
The ZWO Ha 7nm Filter filter has a bandpass of 7nm and passes light at 656nm wavelength, light transmission rate comes up to 80%. Best choice of narrowband H-alpha astrophotography filter for high-contrast imaging and revealing rich details of the nebula even in areas with strong light pollution, just prepare to experience the infinite fun with it!
Technical Data
- FWHM：7±0.5nm
- Fine-optically polished to ensure accurate 1/4 wavefront over the both surfaces
- About 90% transmission at H-alpha line 656nm (H-Alpha filter )
- Infrared wavelength 700-1100nm cut-off
- <0.1% transmission of off-band, OD3(Optical Density)
Transmission Curve
