The Antlia H-Beta 3nm Pro filter optimizes the width at half maximum (FWHM) to a bandwidth of 3nm. Thanks to this narrow bandwidth, the filter greatly improves the contrast of emission targets by reducing unwanted background noise. It achieves an impressive transmission of 88% at 486.1nm, guaranteeing a powerful signal and well-defined nebular structures.
Out-of-band blocking is rated OD5 (0.001%), ensuring an excellent signal-to-noise ratio (SNR) and effectively cutting interference from other wavelengths. Its clean spectral profile is designed to minimize halos around bright stars.
The series includes Ha, SII, OIII and H-Beta filters, which capture extremely narrow data on four channels, offering great flexibility of combination in post-processing to meet a variety of needs.
| Parameter | Value |
|---|---|
| Type | H-Beta |
| FWHM | 3nm |
| Center wavelength (CWL) | 486.1nm |
| Maximum transmission | 88% |
| Out-of-band discharge | >OD5 (0.001%) from 300 to 1100nm |
| Thickness | 2mm ±0.05mm |
| Substrate | Optics, unglued monoblock |
| Surface quality | S/D 60/40 (MIL-O-13830 standard) |
| Transmitted wavefront | λ/4 or better |
| Parallelism | < 30 arcsec |
| Ring | 2'' (M48x0.75) |
| Warranty | 3 years against delamination |
NEVER LOOK DIRECTLY AT THE SUN WITH THIS FILTER. Serious eye damage may occur.
Antlia also offers dual-band filters for color cameras (OSC): the ALP-T Dualband Ha&OIII 3nm and the SII&Hb 3.5nm. Their synergy produces extremely detailed images on all four channels: Ha, OIII, SII and Hb. These spectra can be recombined in classic or creative color palettes: H-O-Hb, S-H-O, H-S-OHb, H-O-O, etc.
