ANTLIA Narrowband 7nm H-alpha Prime Filter - 36mm Unmounted (glass only)

ANTLIA Narrowband 7nm H-alpha Prime Filter - 36mm Unmounted (glass only)

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 CWLHa 656.3nm lines that provides 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.

Application and Performance:

• 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
• A single substrate to eliminate internal reflections Narrowband Objects: H-alpha,NII Emission Nebulae, Planetary, Wolf Rayet Nebulae and Supernova Remnants
• Use in light polluted areas and dark sites
• All Antlia unmounted filters are edge blackened to eliminate internal reflections from stray light
• Superior optical reliability reduces post image processing
• This filter is effective for deep sky objects that contain H-alpha and NII emissions

Technical Specifications:

• Basic Substrate: Optical, Single / Non-glued substrate
• Filter Thickness: 2mm+/-0.05mm for Dia36mm unmounted
• FWHM (Full width at half maximum): 7nm
• CWL (Central Wavelength): 656.3nm
• Peak Transmission: ＞90%
• Blocking: > 4OD(0.01% 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
• Warranty: 3-years against delamination

Spectrum Curve: