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Antlia H-Alpha 7nm Prime Filter - 36mm
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Antlia H-Alpha 7nm Prime Filter - 36mm

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SKU: ANT-HA7P-36
$173.80
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Antlia H-Alpha 7nm Prime Filter - Narrowband - 36mm Unmounted

The Antlia H-alpha Prime narrowband filter optimizes the FWHM (full width half maximum) to 7nm bandpass. The suppression of optical density is (OD) 4 on unwanted wavelengths. The excellent optical coating characteristics found in the Antlia 3nm Pro series has been incorporated into the 7nm Prime narrowband filters. The result is that these filters deliver superior SNR (signal to noise ratio) and better contrast in your images.

Antlia H-alpha 7nm Prime filters are designed to deliver 90% transmittance at the CWL Ha 656.3nm lines, providing you with the maximum signal and well-defined nebulae structures. Besides, it is wide enough (7nm bandwidth) to pass emission lines at NII 654.8nm and NII 658.3nm. The out of band blocking specification is rated OD4 (0.01%) which delivers an excellent SNR (signal to noise ratio) and effective cut-off rate to minimize interference from other wavelengths. Improved sharp cut off astrophotography 7nm Prime filters are designed to minimize halos around bright stars. Antlia 7nm Prime filters can be used with nearly all systems as fast as f/2 with minimal loss in emission signal and meets the requirements of fast optics.

Antlia 7nm H-Alpha Prime Filter Specifications

  • FWHM: 7nm
  • CWL: 656.3 nm
  • Peak Transmission: >90%
  • Blocking: 4 OD (0.01% out of band blocking) @ 300-1000nm
  • Filter Thickness: 2mm +/- 0.05 mm
  • Basic Substrate: Single, non-glued optical 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
  • Size: 36mm Unmounted

Antlia 7nm Ha Prime Filter Features

  • 90% transmittance at Central Wavelength H-alpha 656.3nm line
  • FWHM is wide enough to pass both H-alpha and NII lines
  • With wider FWHM, 7nm Prime narrowband filters can be used with fast optics of f/2 with minimal loss of signal
  • Steep spectral profile minimizes halos around bright stars
  • Narrowband Objects: H-alpha & NII Emission Nebulae, Planetary, Wolf Rayet Nebulae and Supernova Remnants
  • Use in light polluted areas and dark sites
  • All Antlia Narrowband filters are edge blackened to eliminate internal reflections from stray light
  • Superior optical reliability reduces post image processing
  • This filter is not suited to deep sky objects that do not contain Ha and NII emissions.