GSO Dobson 8" Deluxe Telescope

The GSO 8" Dobson is a substantial Newtonian reflector telescope that delivers outstanding performance for its price point. With a primary mirror diameter of 250 mm, an f/6 focal ratio, and a 1200 mm focal length, this instrument provides impressive capabilities for deep-sky observing. Nebulae and other extended celestial targets appear in remarkable detail under dark-sky conditions, with hundreds visible and many offering detailed observation. Planetary views are exceptionally bright and reveal significant surface features. Excellent for tracking comets and detecting faint variable stars, this telescope is a strong choice for a range of astronomical pursuits.

Mounting is provided by a Dobsonian azimuthal mount designed for simple, intuitive operation, utilizing both vertical and horizontal motions for easy navigation. The sturdy materials and reliable tube mounting ensure excellent stability, reducing susceptibility to wind and incidental vibrations. A precision roller bearing installed between the lower base plates allows the GSO-manufactured Dobsonian mount to move smoothly and accurately.

GSO telescopes are well-known for their superior Crayford focuser, crafted from CNC-machined aircraft-grade aluminum. Precision focusing is enabled by a 1:10 micro-adjustment screw, while a separate tensioning screw customizes resistance to the user's preference, and a locking option maintains the focuser position as required.

Delta Optical-GSO Dobson models include a built-in fan mounted beneath the primary mirror. Powered by 12 V, this fan promotes efficient air circulation around the mirror and accelerates the cooling process.

Basic features of the telescope:
- Primary mirror diameter: 200 mm with a focal length of 1200 mm,
- Primary mirror reflectivity of 94%,
- Integrated fan to enhance primary mirror cooling,
- Durable GSO Crayford microfocuser (1:10 ratio), expertly manufactured for zero play and capable of supporting accessories weighing up to 3 kg,
- 30 mm Erfle eyepiece, ideal for wide-field viewing of nebulae, star clusters, and expansive sky regions. This eyepiece offers a 65-degree apparent field of view, delivering a 2.2-degree true field,
- 9 mm Plossl eyepiece achieves crisp, sharp imagery at higher magnifications, well-suited for lunar and planetary observation,
- Tripod mounting ensures precise tube suspension using robust steel rods. The dual-side compression mechanism facilitates highly accurate adjustment.

The set includes:
- 2" eyepiece, 30 mm,
- 1.25" eyepiece, 9 mm,
- 35 mm extension tube,
- 8x50 straight-through finder,
- cooling fan for the primary mirror accompanied by a battery holder.

Technical data
Optical system of the telescope: Newtonian
Mount type: Dobsonian
Max. theoretical magnification: 305x
Min. theoretical magnification: 29x
Magnification with eyepiece 1: 40x
Magnification with eyepiece 2: 133x
Stellar magnitude limit: 14.0 mag
Focal ratio: 5.9
Eyepiece focuser: Crayford microfocuser 1:10
Finder: optical 8x50 straight
Focal length of eyepiece 1: 30 mm
Focal length of eyepiece 2: 9 mm
Objective focal length: 1200 mm
Focuser diameter: 2" with 1.25 reduction
Objective diameter: 203 mm
Tube diameter: 230 mm
Tripod height: 600 mm
Weight: 20 kg
Manufacturer: Guan Sheng Optical, Taiwan