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Astronomik H-Alpha 12 nm CCD Filter - 27 mm Round - HA12-27

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SKU: ASF-HA12-27

Astronomik H-Alpha 12 nm CCD Filter - 27 mm Round

  • 27 mm round Astronomik H-Alpha 12 nm CCD Filter designed for astrophotography
  • Developed with the most important technical principles in mind, this filter offers the optical performance you want for deep sky imaging with CCD cameras
  • Allows H-Alpha light emissions to pass while blocking almost the entire remainder of the visual spectrum plus IR
  • 12 nm FWHM bandwidth
  • Ideal for imaging planetary nebulae and supernova remnants, the Astronomik H-Alpha 12 nm CCD Filter rejects all undesired light pollution
  • Made in Germany, a country recognized for producing optics of superior quality!


More About Astronomik H-Alpha 12 nm CCD Filters

For CCD astrophotography, this Astronomik 27 mm Round H-Alpha 12 nm Filter is the ideal narrowband filter. It has a 12 nm full width at half maximum (FWHM) to allow the use of very fast optics with standard CCD cameras. The f/number application range stretches from 1:2.8 to 1:15. While transmission losses and chromatic distortion can be a problem with other filters, they only become an issue with this filter when extremely bright aperture ratios of 1:2 and more come into play. It should also be noted that the Astronomik 27 mm H-Alpha 12 nm Filter has a transmission of up to 99%. Another advantage of this filter is that finding a guide star is more convenient when used with cameras that have a built-in autoguider.

Astronomik's H-Alpha 12 nm Filter enhances the contrast between objects, in this case between targeted objects with H-Alpha emission lines and the skyglow background. This filter also provides total suppression of emission lines from artificial sources such as mercury and sodium-vapor from street lamps, making it an excellent light pollution filter! Because of the high optical quality of the Astronomik H-Alpha 12 nm substrate, you won't be able to tell the difference between the razor sharp stars seen with a camera or with your regular telescope.

This 27 mm Round H-Alpha 12 nm CCD filter from Astronomik completely obstructs all undesired wavelengths in the visual and IR spectral areas. Like all Astronomik filters, it is parfocal with all other Astronomik filters. It contains a very thin substrate and is diffraction limited for maintaining your telescope's optical performance. This filter is also entirely resistant to scratching as well as the effects of high humidity and aging. Astronomik filters arrive in a durable plastic storage container of excellent quality.

Transmission Specifications

  • Over 97% H-Alpha line transmission
  • Blocks virtually the entire remainder of the visible spectrum
  • Blocks undesirable Infrared wavelengths


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