Coronado SolarMax II 40mm Double Stacking Etalon

A fantastic upgrade to your PST! Designed to attach to an existing etalon, creating a double-stack system Includes RichView tuning to boost contrast on the solar feature being observed Threads directly onto the front cell of a PST, narrowing the bandpass to <0.5 Angstroms (Å)! Not to be used standalone, must be combined with existing PST or SolarMax 40 and blocking filter (BF) This add on etalon filter reduces the normal bandwidth of a PST, SolarMax 40 telescope, or filter set (etalon and Blocking Filter combination) from the single stack 0.7-1 Angstrom (Å) performance to a more restrictive 0.5Å, increasing visibility of surface detail and active regions on the Solar disc. Note that this etalon MUST be combined with a primary SolarMax 40 filter and blocking filter, complete Coronado SolarMax 40 telescope, or a PST telescope. Includes patented RichView tuning assembly, which allows direct tuning of the primary filter etalon. This provides a contrast boost for the best possible vie