Celestron Schmidt-Cassegrain telescope SC 235/2350 C925 OTA (7939)

The Schmidt-Cassegrain optical system combines a long focal length with a compact optical tube assembly (OTA), making it lightweight and easy to transport. Light first passes through an aspherically figured Schmidt corrector plate, which directs it onto a spherical primary mirror. The light is then reflected to a secondary mirror and redirected through a central hole in the primary mirror to the focuser at the bottom of the OTA. This closed system prevents air turbulence that could degrade image quality and protects the optics from dust. The Schmidt corrector plate is multi-coated, ensuring bright, high-contrast images with minimal stray light reflections.

This telescope produces sharp, high-contrast images, making it ideal for planetary observation. The Schmidt-Cassegrain design is versatile and suitable for both visual observation and astrophotography, with a wide range of optional accessories available. It can also be used for occasional terrestrial observations, such as birdwatching at close range. With an aperture ratio of f/10, this telescope is particularly well-suited for astrophotography.

The primary mirror focusing mechanism provides a large range of focus adjustments, allowing compatibility with virtually any common accessory. To minimize "mirror shift," two pre-loaded ball bearings are used in the focusing mechanism. High-quality materials such as CNC-milled aluminum components, cast steel, and stainless steel ensure durability while keeping weight low, eliminating the need for heavy mounts often required by other designs.

Key Features of the Optics:

• Long focal length with a short OTA

• Lightweight aluminum construction

• High-quality StarBright XLT multi-coating

• Closed system for dust protection

• Pre-loaded ball bearings to reduce mirror shift

Included with the Telescope:

• Optical Tube Assembly (OTA) with 235mm aperture and 2350mm focal length

• 25mm Plössl eyepiece (1.25")

• 1.25" star diagonal (90°)

• Mounting rail (Losmandy-style prism rail)

• 6x30 straight-view finder scope

Specifications

Optics:

• Type: Reflector (Schmidt-Cassegrain)

• Aperture: 235mm

• Focal Length: 2350mm (f/10)

• Resolving Capacity: 0.49 arcseconds

• Limiting Magnitude: 13.7 mag

• Light Gathering Power: 1130x compared to the human eye

• Maximum Useful Magnification: 470x

• Tube Length: 559mm; Construction: Full tube; Weight: 9.4kg

• Coating: StarBright XLT

Reflector Details:

• Secondary Mirror Diameter: 85.1mm

• Secondary Mirror Obstruction: 36%

Focuser:

• Type: SC thread with 2" eyepiece connection

Mount:

• Type: OTA only (no mount included)

Included Accessories:

• Eyepiece (1.25"): Plössl 20mm eyepiece

• Finder Scope: 6x30 straight-view finder scope

• Diagonal Mirror: 1.25", 90° star diagonal

• Mounting Rail: Losmandy-style prism rail

General Information:

• Series: OTA

• Total Weight: 9.1kg

Recommended Use

This telescope is designed for advanced users and observatories due to its high-quality optics and compatibility with astrophotography equipment but is not recommended for beginners. It excels in lunar/planetary observation, deep-sky exploration of nebulae and galaxies, and astrophotography but is not suitable for solar observation unless used with an appropriate solar filter.