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Astronomik H-Alpha 12 nm CCD Filter - 2" Round Mounted - HA12-2

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SKU: ASF-HA12-2

Astronomik H-Alpha 12 nm CCD Filter - 2"


  • This round photographic filter is mounted in a 2" threaded cell
  • Made to the highest technical standards for the finest optical performance necessary for imaging deep sky objects
  • Lets H-Alpha emissions pass while blocking close to the entire remainder of the visual spectrum as well as IR
  • 12 nm FWHM (full width at half maximum)
  • Perfect for imaging planetary nebulae and the remnants of supernovae, the Astronomik H-Alpha 12 nm filter obstructs all unwanted light pollution
  • Made in Germany, a country renowned for producing high quality optics!


More About the Astronomik 2" H-Alpha 12 nm CCD Filter


This Astronomik 2" Round Mounted H-Alpha 12 nm CCD Filter is the optimal narrowband filter for CCD astrophotography. With a 12 nm FWHM, this filter is ideal for standard CCD cameras, allowing very fast optics to be employed. The f/number application range is spread from 1:2.8 to 1:15. The only time you'll have to be concerned with transmission losses and chromatic distortions, which can be an issue with other filters, is when excessively bright aperture ratios of 1:2 and more are involved. It should also be acknowledged that this filter has an up to 99% transmission. An additional asset of this 12 nm filter is the more convenient availability of guiding stars for cameras with an integrated autoguider.

The contrast between objects with H-Alpha emission lines and the skyglow background is enhanced by the Astronomik H-Alpha CCD Filter. In addition, this filter completely cuts off light from spurious sources such as the mercury and sodium-vapor lines from street lamps, making it an outstanding light pollution filter! Due to the Astronomik CCD H-Alpha substrate's high optical quality, you'll see the same razor sharp stars you'd see if you were using your regular telescope.

Delivered in a superior quality, long-lasting plastic storage box, this 2" Round Mounted H-Alpha 12 nm CCD Filter completely blocks out all undesired wavelengths in the visible light and IR spectral bands. As with all Astronomik filters, this filter is parfocal with all filters from Astronomik. Diffraction limited, it will not lessen the optical capabilities of your telescope. This filter is also highly resistant to blemishes caused by scratching, aging, and high humidity.

Transmission Specifications


  • 97+% transmission for the H-Alpha line
  • Blocks nearly the whole remainder of the visual spectrum
  • Blocks unwanted wavelengths in the infrared


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