Coronado 90mm SolarMax III Double Stack Solar Telescope - BF15 - 324012

Coronado 90 SolarMax III Double Stack Solar Telescopewith RichView Tuning & 15 mm Blocking Filter Coronado's SolarMax Series now includes the sophisticated 90 mm SolarMax III Double Stack Hydrogen-Alpha Solar Telescope! The 90mm double stack refractor has a focal ratio of f/8.9 and an 800mm focal length. It is equipped with two 90mm external hydrogen-alpha etalons, providing higher contrast and sharper features than a double stacked solar scope fitted with an internal and external filter. The external etalons work in conjunction with a 15mm blocking filter situated in a 1.25" star diagonal. Together, the tunable external etalons and the blocking filter produce a < 0.5 Angstrom passband which yields an optimal balance of prominence and surface detail. Another great feature of the double-stacked Coronado 90 SolarMax III is the ability to view not only in the <0.5A bandwidth but in the <0.7A bandwidth as well! To accomplish this you would remove the first etalon (the one at