Antlia H-alpha 3 nm Pro 1,25" narrowband filter

Antlia H-alpha 3 nm Pro Astrophotography Filter - 1.25" Diameter

The Antlia H-alpha 3 nm Pro 1.25" is an advanced narrowband filter tailored for astrophotography enthusiasts. Specifically engineered to capture the red light at a precise wavelength of 656.3 nm, it excels in photographing emission nebulae by isolating the light emitted by ionized hydrogen atoms.

Exceptional Light Filtering and Transmission

With an ultra-narrow half-bandwidth of just 3 nm, this filter stands out for its ability to effectively block unwanted light from common sources like sodium and mercury lamps. Its high transmission rate for the Hα spectral line makes it an indispensable tool for astrophotographers aiming to capture detailed and vivid nebulae images.

Note: This filter is designed for astrophotography and is not recommended for visual observations.

Key Features

• Crafted using a high-quality Schott substrate, optimized for maximum transmission of 656.3 nm radiation.
• Compatible with astrographs that handle light intensities down to f/3, such as RASA or Hyperstar.
• Features an exceptionally narrow full-width half-maximum (FWHM) of 3 nm.
• Provides an equivalent optical density (OD5), ensuring a remarkable 99.999% efficiency in blocking light pollution.

Technical Specifications

• Filter Type: Bandpass Filter
• Filter Diameter: 1.25"
• Filter Thickness: 2 ± 0.05 mm
• Filter Shape: Round
• Transmitted Bands: Hα (656.3 nm)
• Peak Permeability (CWL): 656.3 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 (per MIL-O-13830 standard): 60/40
• Parallelism: 30"
• Execution Accuracy (RMS): λ / 4

Kit Components

• Antlia H-alpha 3 nm Pro 1.25" Filter

Warranty

This filter is backed by a 3-year manufacturer's warranty, covering issues related to delamination of the filter and substrate.