GSO 10" F/12 M-LRC Classical Cassegrain Truss Carbon OTA

The Cassegrain telescope, once considered extinct, is making a comeback in the astronomy community, thanks to the efforts of the Taiwanese GSO factory. With its unique features and exceptional performance, the Cassegrain telescope is gaining attention once again and is expected to establish a lasting presence.

One of the notable advantages of the Cassegrain design is its ability to dissipate heat more effectively than Schmidt-Cassegrain and Maksutov-Cassegrain telescopes, similar to RC Newtonian telescopes. Additionally, it operates solely on reflection, eliminating residual chromatic aberration caused by light diffraction, which sets it apart from RC and Newtonian telescopes.

The Cassegrain telescope boasts a longer focal length compared to typical RC or Newtonian telescopes and shares similarities with Maksutov telescopes in terms of its parametric properties. Its compact structure, resembling that of RC and Mak telescopes, offers convenience and portability to astronomers.

Another advantage of the Cassegrain design is the absence of a lens system, making it suitable for infrared photography. Furthermore, its long focal length simplifies the collimation procedure, addressing a common challenge encountered with RC telescopes, particularly when used as an exit telescope.

The Cassegrain system comprises a main mirror with a rotational paraboloid shape and a secondary mirror that resembles a segment of a rotational hyperboloid. While these surfaces have traditionally posed challenges in manufacturing, the GSO factory has overcome these difficulties. The long focal length, which is often considered a drawback, actually offers benefits such as eliminating flaws at the field's edges and providing a high reproduction scale for photography and observations.

The Cassegrain telescope is versatile and well-suited for various purposes, including visual observations, planetary astrophotography, compact deep-sky astrophotography with highly sensitive cameras, as well as infrared and ultraviolet photography.

Technical Specifications:

• Optical Design: Cassegrain (aka classic Cassegrain)
• Lens Diameter: 250 mm (10 ")
• Focal Length: 3000 mm
• Focal Ratio: f/12
• Main Mirror: Parabolic shape with a minimum reflection coefficient of 96%, hardened with quartz
• Secondary Mirror: Hyperbolic shape with a minimum reflection coefficient of 96%, hardened with quartz
• Collimation Mark: Yes, located on the secondary mirror
• Obstruction: 33%
• Focuser: 3.25" M-LRC (dual-speed linear bearing Crayford)
• Tube Construction: Carbon truss
• Outer Diameter: 400 mm
• Tube Length: 690 mm
• Weight: Approximately 17 kg (including accessories)
• Factory Shipping Packaging: 92 x 51 x 56 cm / 22 kg

The Cassegrain telescope comes with a 24-month guarantee, ensuring reliability and customer satisfaction. With its exceptional optical design and advanced features, this revived Cassegrain telescope from the GSO factory promises to provide astronomers with an outstanding instrument for their observations and astrophotography endeavors.