The Antlia H-Beta Pro narrowband filter features a precisely tuned 3nm Full Width at Half Maximum (FWHM), which boosts contrast by significantly reducing unwanted background light. With a high transmission rate of 88% at the 486.1nm wavelength, the filter captures strong signal levels and reveals well-defined nebular structures.

It blocks out-of-band wavelengths with an OD5 (0.001%) rating, ensuring an excellent signal-to-noise ratio and minimising interference from nearby spectral lines. The sharp cut-off profile also helps reduce halos around bright stars, delivering cleaner and more detailed images.

The Antlia 3nm Pro series includes H-alpha, SII, OIII, and H-Beta filters. Together, they enable astrophotographers to collect exceptionally narrow-band data across four key emission lines, offering greater flexibility in post-processing and supporting a wide range of imaging styles and palettes.

Application and Performance:

• The ultra-narrow 3nm bandwidth delivers high transmittance and maximises contrast.

• The steep spectral profile reduces halos around bright stars.

• The single optical substrate eliminates internal reflections in the filter’s design.

• This filter targets H-Beta emission nebulae for optimal performance.

• It delivers reliable results in both light-polluted and dark-sky locations.

• During bright lunar phases, it blocks moonlight effectively and extends imaging time.

• The filter works with fast optical systems down to f/3, with minimal signal loss.

• Antlia edge-blackens all unmounted narrowband filters to suppress stray light reflections.

• Its optical precision reduces the need for extensive post-processing.

• Use this filter only with deep-sky objects that emit in the H-Beta wavelength for best results.

The filter ring features a 2″ (M48×0.75) thread. Its ultra-thin filter cell maximises the clear aperture and helps minimise vignetting in fast optical systems. A durable black anodised finish protects the housing, while laser-engraved markings ensure long-term visibility without fading.

Important: This filter isn’t suitable for solar imaging or night-time visual observation.

Warning: Never look directly at the Sun using this filter. Ignoring this safety warning can result in serious and permanent eye damage.

Antlia also offers dual narrowband filters designed specifically for one-shot colour (OSC) cameras. These include the ALP-T Dualband Ha&OIII 3nm and the SII&Hb 3.5nm filters. When used together, they enable the capture of narrow-band spectral data across four channels—H-alpha, OIII, SII, and H-beta. You can separate and recombine these channels during post-processing to create a wide range of colour palettes. This flexibility allows you to boost luminance contrast in RGB-balanced images or produce false-colour combinations such as H-O-Hb, S-H-O, H-S-OHb, and H-O-O to suit your creative and scientific goals.