Svbony SV227 2" HSO / SHO 5 nm Filter Set (Svbony, SKU: W9187DC-W9187DA-W9187DB) is a complete set of three narrowband filters designed for emission nebula astrophotography. The set includes H-Alpha, OIII, and SII filters with a 5 nm bandwidth, enabling high-contrast imaging of deep-sky objects even under light-polluted skies.

Key features

• complete SHO narrowband filter set (H-Alpha, OIII, SII)
• 5 nm bandwidth for high-contrast astrophotography
• designed for emission nebulae and deep-sky imaging
• high peak transmission of ≥90%
• effective blocking of unwanted wavelengths at ≥OD5
• manufactured from high-quality optical glass
• coatings optimized for long-exposure imaging

Elements of the set

• Svbony SV227 SII 2" 5 nm filter (CWL 672 nm)
• Svbony SV227 H-Alpha 2" 5 nm filter (CWL 656.3 nm)
• Svbony SV227 OIII 2" 5 nm filter (CWL 500.7 nm)

Technical specifications

• filter type: SHO narrowband
• size: 2"
• thread: M48 × 0.75
• wavelength range: 300–1000 nm
• bandwidth (FWHM): 5 nm
• central wavelength (CWL): 672 nm (SII), 656.3 nm (H-Alpha), 500.7 nm (OIII)
• peak transmission: ≥90%
• blocking: ≥OD5
• clear aperture: 44 mm
• substrate thickness: 1.85 mm
• surface quality: 60/40
• surface parallelism: 1/4λ
• parallelism: 30"
• weight per filter: 12.5 g