Description
Note - this filter is discontinued
Highlights
- Highspeed Narrowband Filter, 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. 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 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.