Antlia ALP-T Dualband 3nm SII&OIII Highspeed 2"

Antlia ALP-T Dual Band 3 nm SII/OIII Highspeed Filter 2" (Antlia) is a dual-band narrowband filter designed for emission nebula astrophotography with fast optical systems. It enables the simultaneous capture of ionised sulphur SII and ionised oxygen OIII emission. The Highspeed version uses pre-shifted transmission bands that compensate for the shift towards shorter wavelengths occurring at large angles of incidence.

Key features

• two narrow transmission bands with a nominal FWHM of 3 nm for the SII and OIII lines
• simultaneous capture of ionised sulphur SII and ionised oxygen OIII signals
• Highspeed version designed for fast optical systems
• pre-shifted transmission bands compensating for blueshift caused by a large angle of incidence
• construction developed primarily for use with OSC colour astronomy cameras
• suitable for use with monochrome cameras as a dual-band luminance filter
• reduction of artificial light, moonlight and atmospheric airglow in the captured data
• improved contrast of nebular structures and signal-to-noise ratio
• ability to supplement Ha/OIII filter data with SII-band data when creating false-colour compositions
• multi-layer coatings on both sides and anti-reflection coatings reducing internal reflections and halo formation

Set contents

• Antlia ALP-T Dual Band 3 nm SII/OIII Highspeed Filter 2"

Technical specifications

• filter type: dual-band narrowband astrophotography filter
• version: Highspeed with pre-shifted transmission bands
• transmitted emission lines: SII and OIII
• nominal SII line wavelength: 672.4 nm
• nominal OIII line wavelength: 500.7 nm
• nominal SII FWHM bandwidth: 3 nm
• nominal OIII FWHM bandwidth: 3 nm
• primary compatibility: OSC colour astronomy cameras
• additional compatibility: monochrome cameras
• optical application: fast astrophotography systems
• application: emission nebula imaging
• cell size: 2"
• cell thread: M48 × 0.75
• cell finish: black anodising and laser markings
• suitable for visual observation: no
• suitable for solar imaging: no

The Antlia ALP-T Dual Band 3 nm SII/OIII Highspeed Filter enables the simultaneous capture of two emission bands in a single exposure while maintaining useful signal transmission in fast astrophotography setups.