H-alpha System 2 FWHM 0.75A (0.075nm)
The BelOptik H-alpha system 2 is a individual modified solution for star friends, which have an ultra narrow bandpass H-alpha filter system with blocking filter. These systems is for connecting on telescopes with greater free aperture.
With 4“ or 5“ free aperture with effective collimated 3000mm or 3600mm focal length (F30 aperture ratio) are amazing detailed solar observations possible with high magnification.
These great images were taken by Martin from Astroclub Radebeul on Zeiss AS 150/2250mm Coudé refractor telescope with 125mm ERF, Coronado BF30 blocking filter, telecentric lens assembly with 35mm etalon (f=3150mm), camera DMK31 from Imaging Source