The Antlia H-Beta Pro narrowband filter optimizes the full width at half maximum (FWHM) to a 3nm bandpass. As the bandwidth narrows, these 3nm Pro narrowband filters enhance the contrast of emission targets by effectively reducing unwanted background signals. Designed to achieve an impressive 88% transmission at the 486.1nm line, Antlia H-Beta 3nm Pro filters provide maximum signal and well-defined nebula structures. The out-of-band blocking specification is rated at OD5 (0.001%), ensuring excellent signal-to-noise ratio (SNR) and effective cutoff rates to minimize interference from other wavelengths. These improved sharp cutoff astrophotography 3nm Pro filters are specifically engineered to reduce halos around bright stars.
The Antlia 3nm Pro series currently comprises Ha, SII, OIII, SII and H-Beta filters that capture exceptionally narrow data from four channels, enabling a greater range of combinations in post-production to meet your diverse requirements.
The main features and application
High transmittance and smallest bandwidth to maximize contrast
Steep spectral profile minimizes halos around bright stars
A single substrate to eliminate internal reflections
Narrowband Objects: H-Beta Emission Nebulae
Use in light polluted areas and dark sites
Extend imaging time when the moon is up
All Antlia narrowband Pro filters can be used down to f/3 with minimal loss of signal
All Antlia Narrowband filters unmounted are edge blackened to eliminate internal reflections from stray light
Superior optical reliability reduces post image processing
This filter is only effective for deep sky objects that contain H-Beta emissions
Technical Specifications:
| Hydrogen Beta |
FWHM (Full width at half maximum): | 3nm |
CWL (Central Wavelength) | 486.1nm |
Peak Transmission | 88% |
Blocking | > 5 OD (out of band blocking) @ 300-1100nm |
Filter Thickness | 2mm+/-0.05mm |
Basic Substrate | Optical, Single / Non-glued substrate |
Surface Quality | S/D (scratch/dig)= 60/40 (Refer to MIL-O-13830 |
Transmitted Wavefront | Lambda/4 or better. |
Parallelism | less than 30 arcsec |
Filter Ring | 2'' (M48*0.75) |
Spectrum Curve:
Warranty: 3-years against delamination
Available Size：
Mounted 2''
Filter Ring:
2'' (M48*0.75)
Ultra-thin filter cell to minimize vignetting by maximize possible clear aperture
Black Anodized Finish
Laser Engraving No Fading
Not Recommended:
Solar imaging
Night visual observation
Not Permitted:
DO NOT LOOK AT THE SUN WITH THIS FILTER DIRECTLY
Serious eye damage will result if you fail to observe the warning.
