Set of Antlia ALP-T Dualband SII&H-beta and Ha&OIII filters (2″)

Antlia ALP-T Filter Kit – SII&H-Beta and OIII&H-Alpha

The Antlia ALP-T 5nm kit offers a complete solution for capturing the main emission lines of the deep sky: SII (ionized sulfur), Hβ (beta hydrogen), OIII (doubly ionized oxygen), and Hα (alpha hydrogen). Designed to maximize contrast, enhance the resolution of fine details, and reduce light pollution, these filters enable the capture of spectacular images with both color cameras (OSC) and monochrome sensors.

Filters included in kit

• SII&H-Beta Filter – Centered at 672.4 nm and 486.1 nm
• Ha&OIII Filter – Peak transmission at 500.7 nm and 656.3 nm

Key features

• Ultra-narrow bandwidth of 5nm for each filter
• High transmission: approximately 85% to 92%, depending on the emission line
• OD4.5 out-of-band suppression (300nm to 1100nm) for maximum contrast
• Compatible with DSLR, CMOS and CCD cameras
• Designed for high-speed optics without noticeable band offset
• Ion Gun Assisted Deposition coating for maximum durability
• Effective NIR blocking

Ideal applications

• Astrophotography in false color palettes (H-O-Hb, S-H-O, H-S-OHb, H-O-O)
• Imaging emission nebulae, supernovae, Wolf-Rayet regions
• Use under polluted or lightly polluted skies (Bortle 1 to 8)
• Create separate channels to enrich traditional RGB compositions

Technical specifications

• Thickness: 2mm ± 0.05mm
• Optical quality: S/D 60/40
• NIR removal: up to 1100 nm
• Available sizes: mounted 2” (M48x0.75) or unmounted Ø36mm
• Ultra-thin cell to minimize vignetting
• Black anodized finish and durable laser engraving

Why include H-Beta in addition to OIII?

While the OIII line is well covered by the RGGB arrangement of the color cameras, Hβ (486.1 nm) reveals structures that are invisible in OIII or Hα images. Adding the Hβ filter allows you to capture subtle details in nebulae that would otherwise be overlooked, enhancing the spectral richness of the final images and providing greater flexibility during post-processing.

Recommendations for Use

• Recommended for use exclusively in astrophotography
• Not recommended for nighttime visual observation
• It is strictly prohibited to use this filter for solar observation.