ZWO H-Alpha SII OIII filter set 36 mm separate filters

ZWO H-Alpha SII OIII filter set 36 mm separate filters contains three narrowband interference filters (H-Alpha 656 nm, S II 672 nm and O III 501 nm) that suppress light pollution and capture faint nebulae in contrast. Thanks to the bandwidth of 7 nm, you precisely exploit the emission lines of hydrogen, sulfur and oxygen in H II regions, supernova remnants and planetary nebulae. These filters are homofocused with ZWO LRGB sets, so you switch without refocusing.

Key benefits
✓ Narrow-band H-Alpha, S II and O III filters for maximum contrast enhancement
✓ 7 nm half-value bandwidth minimizes ambient light without signal loss
✓ Homofocal design matches ZWO LRGB and color filters; no refocusing
✓ Loose 36 mm filters for any standard filter wheel
✓ Aluminum housing guarantees sturdy, reflection-free mounting

Practical application
Combine with a monochrome ZWO ASI camera and a filter wheel for automatic changes. Capture delicate nebular structures in Orion, Veil and Ring Nebula with exceptional detail and contrast, even under urban skies.

Technical specifications

• Format: 36 mm loose filters
• Filters: H-Alpha 656 nm, S II 672 nm, O III 501 nm
• Bandwidth (half-value): 7 nm
• Transmission: 80 %
• Glass thickness: 2 mm
• Housing: aluminum
• Application: narrowband astrophotography (photographic)