Antlia H-alpha 3 nm Pro 36 mm unmounted narrowband filter

The Antlia H-alpha 3 nm Pro 36 mm filter is a cutting-edge tool designed specifically for professional astrophotography. This filter is adept at capturing the elusive red light emitted by ionized hydrogen atoms with a wavelength of 656.3 nm. Its exceptional capability to register this wavelength is particularly valuable when photographing emission nebulae, making it an indispensable accessory for astrophotographers.

One of the standout features of this filter is its remarkably narrow half-bandwidth of only 3 nm. This characteristic enables the filter to effectively eliminate unwanted components emitted by sodium and mercury lamps while maintaining high transmission efficiency for the crucial Hα spectral line. For astrophotographers, the Hα wavelength holds immense significance, and this filter ensures its optimal capture.

It is important to note that the Hα filter is not recommended for visual observations and is primarily intended for astrophotography purposes.

Key Features of the Antlia H-alpha 3 nm Pro 36 mm Filter:

Bandpass Filter on Premium Schott Substrate: This filter is crafted using a high-quality Schott substrate, ensuring exceptional performance and maximum transmission for radiation at 656.3 nm.

Compatibility with Astrographs: The filter is compatible with astrographs featuring light intensity up to f/3, such as RASA or Hyperstar, enabling seamless integration into various astrophotography setups.

Ultra-Narrow Half-Bandwidth: With a Full Width at Half Maximum (FWHM) of only 3 nm, this filter offers an incredibly narrow transmitted band, enhancing precision in capturing the desired wavelengths.

High Blocking Efficiency: The filter exhibits an equivalent optical density (OD5), resulting in an exceptional efficiency of over 99.999% in cutting out light pollution. It effectively blocks the emission bands of mercury lamps (435.8 nm, 546.1 nm, 577 nm, 578.1 nm) and sodium lamps (598 nm, 589.6 nm, 615.4 nm, 616.1 nm).

Technical Specifications:

• Filter Type: Bandpass Filter
• Filter Diameter: 36 mm
• Filter Thickness: 2 ± 0.05 mm
• Filter Shape: Round
• Transmitted Bands: Hα (656.3 nm)
• Center Wavelength (CWL): 656.3 nm
• FWHM (Half Bandwidth): 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 (as per MIL-O-13830 standard): 60/40
• Parallelism: 30 arc seconds
• Execution Accuracy (RMS): λ / 4

Included Components:

• Antlia H-alpha 3 nm Pro 36 mm Filter

Warranty:

The manufacturer provides a 3-year warranty covering delamination of the filter and substrate, ensuring peace of mind and reliable performance for astrophotographers.