ALP-T Dual Narrowband 3.5nm SII & H-Beta
Antlia
From ~$373.59
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In stock
The Antlia ALP-T Dual Narrowband 3.5nm SII & H-Beta is a dual narrowband filter engineered for color (OSC) camera deep-sky imaging, simultaneously passing the deep red Sulfur-II 672.4nm and blue Hydrogen-Beta 486.1nm emission lines. With an ultra-narrow 3.5nm FWHM bandpass and optical density of 4.5 on unwanted wavelengths, it effectively suppresses light pollution, moonlight, and airglow while delivering high signal-to-noise ratio images with enhanced nebulae contrast. When paired with the Antlia ALP-T Ha&OIII filter, it enables four-channel narrowband imaging for advanced false-color processing and detailed emission nebulae capture from Bortle 1 to Bortle 8 skies.
Specifications
| Filter Mount Size | 2 in |
| Sulfur-II Wavelength | 672.4 |
| Recommended Focal Ratio | f/4 or slower |
| Optical Density on Unwanted Wavelengths | 4.5 |
| Hydrogen-Beta Wavelength | 486.1 |
| Transmitted Wavefront Quality | Lambda/4 or better |
| Designed For | Color (OSC) cameras |
| Bandpass Width (FWHM) | 3.5 |
| Filter Type | Dual Narrowband |
| Coating Technology | Ion Gun Assisted Deposition |