Takahashi TSC-225 - 9" Schmidt Cassegrain F/12 - The clear aperture is 225 mm, 2700 mm focal length and the focal ratio is f/12, allowing the use of a smaller secondary, reduced field curvature and off-axis coma.
The OTA weighs less than 25 pounds, including the built-in Tak 7x50 illuminated finderscope that also functions as a convenient handle for the OTA. The rear cell has two ventilation ports: one holds a dust filter and the
other holds a 12VDC cooling fan.
Takahashi TSC-225 - 9" Schmidt Cassegrain F/12
The corrector was hand-figured and used Schott White German optical glass to 1/8 wave. The mirror is oversized at 235 mm. Quoting from a 1990 brochure: "Each set of optics is hand figured to deliver 1/8 wave to the film plane employs an oversized 235 mm primary mirror.
Only about 100 of these excellent SCTs were produced. These 100 samples are scattered throughout the world.