Baader SunDancer II H-alpha filter

SunDancer II H-alpha filter, 0.60 ±0.1 Ångström The Baader SunDancer II (with heated H-alpha etalon from SolarSpectrum) transforms an existing telescope quickly and easily into a professional H-alpha telescope! For telescopes up to 80mm aperture you do not need any additional accessories: The SunDancer II already includes an achromatic (!) 3x telecentric with T-2 connection; the entire SunDancer is simply inserted between the star diagonal and the eyepiece and connected to a power source. It then automatically heats up to the optimum operating temperature. No readjustment is necessary even during long observations. It is possible to fine-tune the transmission line to adapt to different telescope systems via the control box; it can be quickly shifted into the blue wing of the H-alpha line using the micrometer screw to compensate for the Doppler effect during fast H-alpha events on the sun.