SVBONY H-alpha & OIII 1.25" 3 nm Dual Narrowband Filter SV220

The SVBONY SV220 1.25" dual narrowband filter combines ultra-narrow 3 nm H-alpha and OIII passbands, enabling strong suppression of light pollution and sky background while enhancing emission and planetary nebula detail. Its high transmission and advanced multi-layer anti-halo coatings provide clean, high-contrast data, even when imaging from light-polluted urban environments.
 
A wide cutoff range from 300 to 1050 nm, combined with OD5-level blocking, efficiently eliminates stray wavelengths and significantly improves the signal-to-noise ratio. With peak transmission above 85% in both bands, exposure times can be reduced while maintaining strong signal strength. The filter features a standard M28.5×0.6 thread and a 1.25" cell, ensuring compatibility with most planetary and deep-sky astrophotography cameras.

Key features

• dual 3 nm narrowband filter (H-alpha + OIII) for emission and planetary nebula imaging
• multi-layer low-halo coating – minimized glare and improved contrast
• high transmittance (≥85%) in H-alpha and OIII bands for efficient signal capture
• wide blocking range 300–1050 nm with OD5 average depth
• compatible with 1.25" equipment – M28.5×0.6 thread
• made from lightweight and durable 6061T aluminum
• suitable for small and medium sensor astrophotography cameras

Technical specifications

• filter type: dual narrowband H-alpha + OIII
• size: 1.25"
• ring dimensions: Φ31.75 × 7 mm
• thread: M28.5 × 0.6 mm (single male thread)
• cell material: 6061T aluminum profile
• substrate thickness: 2.0 mm
• clear aperture: 26 mm
• center wavelengths: 500.7 nm (OIII), 656.3 nm (H-alpha)
• bandwidth / FWHM: 3±1 nm
• cutoff range: 300–1050 nm
• cutoff depth: average OD5
• surface quality: 60/40
• transmitted wavefront flatness: PV ≤ λ/4
• parallelism: 30″
• net weight: 7 g