Antlia SII 3 nm Pro 36 mm Unmounted Narrowband Astrophotography Filter

The Antlia SII 3 nm Pro 36 mm Narrowband Filter is a professional-grade astrophotographic filter, expertly designed to capture the specific wavelength of 671.6 nm emitted by double ionized sulfur atoms. This filter is a must-have for astrophotography enthusiasts aiming to capture the stunning details of emission nebulae, showcasing the beauty of the cosmos.

Manufactured with precision and care, the Antlia SII filter is built to meet the highest standards. It undergoes rigorous surface quality tests aligned with strict military standards, ensuring its outstanding performance. Its ultra-narrow bandwidth of only 3 nm effectively eliminates unwanted light from sodium and mercury lamps while maintaining high transmission of the crucial SII spectral line.

Important Note: The SII filter is designed solely for astrophotography. It is not suitable for visual observation and should never be used for solar observation.

Key Features of the Antlia SII 3 nm Pro 36 mm Filter:

• Bandpass Filter: Built on a high-quality Schott substrate, this filter maximizes transmission at a wavelength of 671.6 nm.
• Compatibility: Compatible with astrographs like RASA or Hyperstar, supporting high light intensity up to f/3.
• Ultra-Narrow Half-Width: With a full width at half maximum (FWHM) of only 3 nm, it ensures maximum contrast for astrophotography.
• Optical Density: Features an equivalent optical density of OD5, cutting out light pollution with an efficiency of 99.999%.

Technical Specifications:

• Filter Type: Bandpass Filter
• Filter Diameter: 36 mm
• Filter Thickness: 2 ± 0.05 mm
• Filter Shape: Round
• Transmitted Bands: SII (671.6 nm)
• Peak Transmittance (CWL): 671.6 nm
• Half Bandwidth (FWHM): 3 nm
• Maximum Transmission: > 88%
• Blocked Bands: Mercury Lamps (435.8 nm, 546.1 nm, 577 nm, 578.1 nm), Sodium Lamps (598 nm, 589.6 nm, 615.4 nm, 616.1 nm)
• Light Pollution Blocking Efficiency: > 99.999%
• Equivalent Optical Density for Blocked Lines: OD5 (300 - 1000 nm)
• Surface Quality Index (according to MIL-O-13830 standard): 60/40
• Parallelism: 30"
• Execution Accuracy (RMS): λ/4

Included in the Set:

• Antlia SII 3 nm Pro 36 mm Filter

Guarantee:

The Antlia SII 3 nm Pro 36 mm Filter includes a 3-year manufacturer's warranty, covering any delamination of the filter and substrate. This warranty ensures peace of mind and highlights our confidence in the product's quality.