Baader Planetarium 50.4mm Round f/2 High-speed Narrowband Imaging H-alpha/OIII/SII Filter Set, Unmounted

A 50.4mm Round f/2 High-speed Narrowband Imaging H-alpha/OIII/SII Filter Set, Unmounted, is a specialized set of three filters: H-alpha, O III, and S II. These high-speed narrowband filters are meticulously designed to meet the precise requirements of ultra-fast astrograph optics, specifically for Hyperstar and RASA systems. Traditional narrowband filters often result in significant transmission loss due to the pronounced CWL-shift. In extreme scenarios, the CWL may even shift beyond the FWHM (CWL= Center-wavelength / FWHM= full width half maximum). To counteract this, these filters feature a CWL-preshift that aligns perfectly with f/2 to f/3 optics.

The FWHM of these filters is optimized to ensure maximum contrast, even with the typical line broadening associated with fast optical trains. This makes them an ideal choice for high contrast emission nebulae imaging with fast optics. When compared to standard narrowband filters at f/2, these filters offer a triple S/N-ratio, enhancing the quality of your astro-imaging significantly.

For those using these filters within the f/1.8 to f/3.5 range, the improvement over regular sets of narrowband filters is dramatic. This 50.4mm Round f/2 High-speed Narrowband Imaging H-alpha/OIII/SII Filter Set, Unmounted, is a game-changer for astrophotography enthusiasts, offering unparalleled performance and image quality.