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Astronomik H-Alpha 6 nm CCD Filter - 50 mm Square - HA6-50SQ

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SKU: ASF-HA6-50SQ

Astronomik 50 mm Square H-Alpha 6 nm Filter


  • This Astronomik H-Alpha CCD Filter comes in a 50 mm square configuration
  • Created with the highest technical standards in mind to enable first-rate optical efficiency for deep sky imaging with CCD cameras
  • Lets H-Alpha light emissions be transmitted while obstructing almost the entire rest of the visible spectrum as well as IR
  • FWHM of nearly 6 nm
  • Blocks all undesired light pollution to make this filter ideal for imaging both planetary nebulae and supernova vestiges
  • German-designed for supreme optical quality!


An extremely narrow emission-line filter, the Astronomik 6 nm H-Alpha Filter is best equipped for CCD imaging with instruments as fast as f/3.5. It is not suitable for visual or solar applications. This filter allows h-alpha light from emission nebulae to pass through to your sensor while obstructing the remainder of the spectrum entirely.

With a 6 nm full width at half maximum (FWHM), this filter is optimized to display maximum contrast between objects in the h-alpha spectral area, emission nebulae for example, and the skyglow background. While the 12 nm offers similar functionality, the 6 nm provides higher contrast gain because of its smaller FWHM. As a compromise, some background stars will be dimmed or completely eliminated from the final image. To avoid this, use both the 6 nm and 12 nm filters together to allow for maximum contrast without any reduction in your final image's background quality.

Due to its complete elimination of mercury (Hg) and sodium (Na) emissions lines, the primary culprits of light pollution, the Astronomik 6 nm H-Alpha CCD Filter is a great option for imaging under severely light-polluted skies.

Please note this filter must NEVER be used for solar observing or imaging. Doing so will cause permanent damage to your eyes.