Zero Expansion carbon truss tube design, unique ed innovative primary cell design, four Losmandy type dovetails, primary mirror three fans ventilation.
Model: Ultra CRC 300 ST
Type: Ultra Corrected Ritchey Chretien
Clear diameter: 312 mm
OTA assembly type: Carbon open truss tube / CNC alluminium
Focal lenth: 1680 mm
F / ratio: F/5.4
Optical set glass: Sitall
Interferometric report: Yes
Overall OTA length: 720 mm
Overall OTA diameter: 420 mm
Spot size (@26 mm from axis, w/flattener): 5 microns
The Ritchey-Chretien telescope or RCT is a specialized Cassegrain telescope designed to eliminate coma, thus providing a large field of view compared to a more conventional configuration. An RCT has a hyperboloidal primary and a hyperboloidal secondary mirror. It was invented in the early 1910s by American astronomer George Willis Ritchey (1864-945) and French astronomer Henri Chretien (1879?956). Ritchey constructed the first successful RCT, which had a diameter aperture of 60 cm (24 in) in 1927.
The Ritchey-Chretien design is free of third-order coma and spherical aberration. When focused midway between the sagittal and tangential focusing planes, stars are imaged as circles, making the RCT well suited for wide field and photographic observations. As with the other Cassegrain-configuration reflectors, the RCT has a very short optical tube assembly and compact design for a given focal length. Ritchey-Chretien configurations are most commonly found on high-performance professional telescopes. Recent advances in manufacturing have brought these observatory instruments into the price range of advanced amateurs. Officina Stellare manufactures many of the best examples of these professional quality telescopes--superb for research, photography, and simple visual observing with larger apertures.
We recommend that you seriously consider a professional-level mount to support one of these OTAs--such as Losmandy, Paramount, Plane Wave, etc.
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