GSO Newton Truss 303 mm f/4

Overview

The GSO Newton Truss 303 mm f/4 is engineered for astrophotographers seeking precision, mechanical rigidity and thermal stability. Its carbon structure maintains focus throughout the night, while the 94% reflective BK7 mirror delivers excellent contrast.

Combined with a precise 2" Monorail focuser and dual Losmandy rails, this OTA is built for serious imaging sessions with coma correctors and full-frame sensors.

Technical specifications

• Optical design: Newtonian reflector

• Aperture: 303 mm

• Focal length: 1212 mm (f/4)

• Primary mirror: BK7 parabolic, 94% reflectivity

• Secondary mirror: 88 mm

• Central obstruction: ~29%

• Focuser: 2 inch Monorail with 1:10 fine reduction, 1.25" adapter

• Structure: Carbon truss with CNC aluminum parts

• Tube weight: approx. 23 kg

• Included accessories:

  • 8x50 finder

  • Dual Losmandy rails

  • Dust caps

Mount compatibility

The 23 kg tube is suited for heavy duty equatorial mounts used in astrophotography. Harmonic drive mounts such as the iOptron HAE69B or CEM120 are commonly used for their accuracy and load capacity in remote or observatory setups.

Highlights

• Bright 94% BK7 mirror for high contrast imaging

• Carbon truss design ensures thermal and structural stability

• Monorail focuser supports heavy cameras

• Fast f4 optics ideal for wide field astrophotography

• Suitable for use with harmonic drive equatorial mounts