Antlia ALP-T 3.5nm SII/H-beta Dual-Narrowband Filter - 2" Mounted
Antlia
Antlia ALP-T Dual Narrowband 3.5nm SII & H-b Filter for f/4 & Slower Telescopes - 2" Mounted is a multi-band nebula filter in 2" for nebula imaging and light-polluted skies.
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Specifications
Filter
- Filter type
- Dual-band / multi-band nebula filter
- Filter size
- 2" / Mounted
- Transmission
- 90%
Spectral
- Passbands
- SII 672.4 nm (3.5 nm) / H-beta 486.1 nm (3.5 nm)
- Band count
- 2 bands
- Narrowest bandpass
- 3.5 nm
Specifications
- Thickness
- 2 mm
- Substrate / coating
- Optical single non-glued substrate
Use
- Camera use
- Color or mono astronomy cameras, depending on target and workflow
Astrophotography Fit
Best for emission nebulae with one-shot color cameras, especially from light-polluted skies.
Antlia ALP-T Dual Narrowband 3.5nm SII & H-b Filter for f/4 & Slower Telescopes - 2" Mounted is a midrange multi-band nebula filter (2").
Best for emission nebulae with one-shot color cameras, especially from light-polluted skies.
Choose filter size around the sensor diagonal, telescope speed, and filter-wheel or drawer geometry. Flats are still required; a filter can improve contrast, but it will not rescue tilt, bad focus, or poor calibration.
Best paired with
- One-shot color cooled cameras or modified DSLRs
- Emission nebulae rich in H-alpha, OIII, SII, or H-beta signal
- Filter drawer or wheel sized to avoid vignetting
Not recommended for
- Broadband galaxies, reflection nebulae, or clusters as the main use case
- Monochrome SHO workflows that need separate channels
- Very fast optics unless bandpass shift and halos have been checked
Where To Buy
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| Retailer | Price | Availability | View Offer |
|---|---|---|---|
| Starizona Starizona | $396.00 | In stock Updated 5/12/2026 | View Offer - $396.00 |