RichView™ & T-Max tuning: The H-alpha filter is a so-called etalon. In the etalon, destructive interference of the incident light extinguishes most of the radiation in the visible spectral range. Only the desired wavelength of 656 nanometres passes through.
To ensure that this works, the width of the etalon must be set precisely and readjusted during observation. Point the telescope at the Sun and use the focuser to bring the edge of the Sun into sharp focus. Turn the large rotating ring of the RichView™ system until the structures on the Sun are visible in maximum contrast. You can then use the small Max Tuning wheel to tilt the Etalon slightly until the maximum image brightness is achieved.
