Lunático Astronomía

Baader f/2 Highspeed-Filterset H-alpha / OIII / SII



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Baader f/2 Highspeed-Filterset H-alpha / OIII / SII

  • f/2 Highspeed Filterset consisting of 3 Filter: H-alpha, O III, and S II. Highspeed Narrowband Filter is designed especially for the delicate requirements of extremely fast astrograph optics, in particular, Hyperstar and RASA
  • Conventional narrowband filters cause a heavy loss in transmission due to the strong CWL-shift. In extreme cases, the CWL even does shift out of the FWHM (CWL= Center-wavelength / FWHM= full width half maximum). Therefore these filters have a CWL-preshift which matches f/2 to f/3 perfectly.
  • The FWHM is optimized. In spite of the typical line broadening with such fast optical trains, they are able to deliver maximum contrast.
  • For the first time, these filters allow us to use fast optics really effectively with high contrast emission nebulae imaging. Using these filters between f/1,8 and f/3,5 shows a dramatic improvement compared to any regular set of narrowband-filters.

NGC 1893 – Tadpole Nebula, taken by Andreas Bringmann with Prototypes of Baader f/2 Highspeed-Filterset

Including three filters:

  • H-alpha 7nm Highspeed
  • OIII 8.5nm Highspeed
  • SII 8nm Highspeed

Transmission curve

Technical Data:

FILTER SIZE 1 25 inch 2 inch
MANUFACTURER Baader Planetarium  Baader Planetarium
SKU (#) 2459396 2459400
EAN CODE 4047825032157 4047825032164
WEIGHT (KG) 0.182 0.197
TRANSMISSION RANGE multiple bands (see spectral image) multiple bands (see spectral image)
CWL (CENTRAL WAVELENGTH) 656,3 nm; 502 nm; 673 nm 656,3 nm; 502 nm; 673 nm
AR-COATING dielectrically coated, planeoptically polished dielectrically coated, planeoptically polished
FILTER USAGE CCD, Deep Sky, f/2 Highspeed, H-alpha, O-III, S-II CCD, Deep Sky, f/2 Highspeed, H-alpha, O-III, S-II
FILTER MOUNTED Mounted (LPFC 6mm) Mounted (LPFC 6mm)
TYPE OF FILTER Narrowband Narrowband
SINGLE OR SET? Filter-Set Filter-Set
FILTER SHAPE round round


Available in other sizes and formats. If you do not find the size you want, contact us at

Filter thread

1,25", 2", Ø 31, Ø 50, Ø 50mm. unmounted, 50x50mm., 65x65mm.

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