SVBONY SV227 SHO 1.25″ Narrowband Filter Set (H-Alpha, OIII, SII – 5nm)
The SVBONY SV227 SHO filter set is a complete 1.25″ narrowband astrophotography bundle containing H-Alpha, OIII, and SII filters, each with a 5 nm bandwidth. Designed for deep-sky imaging, this set enables SHO (Hubble palette) workflows while strongly suppressing light pollution and sky glow.

Complete SHO Narrowband Set
This bundle includes three dedicated narrowband filters:
- H-Alpha (656.3 nm) – Emission nebula structure
- OIII (500.7 nm) – Oxygen emission regions
- SII (672.4 nm) – Sulphur emission detail
Together, they allow advanced narrowband processing techniques and false-colour imaging commonly used in deep-sky astrophotography.

5 nm Narrowband Precision
Each filter features a narrow 5 nm passband, providing excellent contrast enhancement by isolating specific emission lines while rejecting surrounding wavelengths. This makes the set suitable for imaging faint nebulae under both light-polluted and dark skies.

High Transmission & Deep Blocking
With peak transmission of ≥90% and a cut-off depth of OD5 or greater, the SV227 SHO filters effectively block unwanted light while maintaining strong signal throughput. This improves signal-to-noise ratio during long-exposure imaging.

Optical Quality & Mechanical Precision
Manufactured from high-quality optical glass with precision coatings, the filters are designed to maintain flatness and parallelism across the imaging field, helping minimise star distortion and focus shift.
Standard 1.25″ Compatibility
Each filter uses a standard 1.25″ thread, making the set compatible with most filter wheels, filter drawers, eyepieces, and camera adapters designed for 1.25″ accessories.
Cut-Off Depth ≥ OD5
A deep blocking level of OD5 or higher ensures effective rejection of out-of-band light, helping deliver cleaner backgrounds and higher contrast results in narrowband imaging.

Deep-Sky Imaging Results
The SV227 SHO filter set is well suited to imaging emission nebulae and other deep-sky objects using monochrome cameras and SHO processing techniques.

Important Notes
- Not suitable for solar observation.
- Not recommended for optical systems faster than f/4.