Enhance Your Astrophotography with Antlia Filters SII 4.5nm Edge

Experience the wonders of the universe like never before with the Antlia SII EDGE narrowband filter. Precision-engineered with a 4.5nm bandpass FWHM (full width half maximum), this filter suppresses optical density (OD)5 on unwanted wavelengths while incorporating the exceptional transmittance characteristics of the Antlia 3nm Pro series. The result? Superior SNR (signal to noise ratio) and enhanced image contrast.

The Antlia SII 4.5nm EDGE filter is meticulously designed to deliver high transmittance at the 671.6nm line, providing maximum signal to reveal the faintest SII nebulae structures in your astrophotography.

Unlike conventional broader narrowband filters that suffer from heavy transmission losses due to strong Center Wavelength (CWL)-shift, our filters guarantee >90% transmission within a 1nm range of the center bandwidth. This means the SII 4.5nm EDGE narrowband filter offers high transmittance compatibility with both long focal ratios and fast optical systems. Blue-shift data further demonstrates its versatility, as Antlia 4.5nm EDGE filters can be used with nearly all systems as fast as f/3 with minimal loss in emission signal.

Key Features:

• High transmittance and narrow bandwidth for maximum contrast.
• Steep spectral profile minimizes halos around bright stars.
• Utilizes a single substrate to eliminate internal reflections.
• Ideal for SII Emission Nebulae, Planetary Nebulae, Wolf-Rayet Nebulae, and Supernova Remnants.
• Suitable for use in light-polluted areas and dark sites, extending imaging time even when the moon is up.
• Compatible with f/3 systems with minimal loss of signal.
• All Antlia unmounted filters are edge blackened to eliminate internal reflections from stray light.
• Superior optical reliability reduces the need for extensive post-image processing.

Please Note:

• This filter is effective for deep sky objects that contain SII emissions only.
• Not recommended for solar imaging or night visual observation.
• DO NOT LOOK AT THE SUN WITH THIS FILTER; serious eye damage may result.

At Antlia, we design filters for astronomy imaging systems with a focus on optimizing out-of-band blocking rate, transmittance, and band-pass parameters to achieve optimum results. Each filter undergoes rigorous individual testing and scanning to ensure the highest performance standards. Our commitment to exceptional quality and affordability sets us apart in the world of astrophotography filters.

Specifications

• Basic Substrate: Optical, Single / Non-glued substrate
• Filter Thickness: 2mm+/-0.05mm for 1.25”
• FWHM (Full width at half maximum): 4.5nm
• CWL (Central Wavelength): 671.6nm
• Peak Transmission: >90%
• Blocking: > 5 OD (0.001% out of band blocking) @ 300-1000nm
• Surface Quality: S/D (scratch/dig)= 60/40 (Refer to MIL-O-13830)
• Transmitted Wavefront: Lambda/4 or better
• Parallelism: Less than 30 arcsec
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