This Classic 8-inch dobsonian from Guan Sheng Optics offers high optical performance at a low price. The optical and mechanical quality are without any compromises.

This classic Dobsonian telescope is one of our best-sellers. 8" Aperture are perfect for Moon and Planets but also for Nebular objects and Galaxies. This telescope is also very transportable and easy to use - an ideal telescope for beginner!
 
What's In The Box
GSO Dobsonian Telescope with ROCKER BASE
Cooling Fan behind the main mirror
8x50 Finder with Achromatic Optics
2" Crayford focuser - reduction from 2" to 1.25"
25 mm Premium Plössl - multicoated
9 mm Premium Plössl - multicoated
35mm 2" extension
Eyepiece and Accessory Tray for Eyepieces
Collimation Tool
Plus a host of Free Items
 
Please Download INSTRUCTION MANUAL in PDF from the link provided below.
Physical Copies of the manual will not be given.

8x50 Finderscope
Powerful 8x50 finderscope, multicoated objective lens. This little telescope will show many objects in direct vision for easy location.
 
Finderscope Bracket
The 8 x 50mm finderscope mounts in a quick release bracket that slips into a pre-installed metal mounting shoe nearer the focuser. The bracket is held in place in the mounting shoe by a single large hand-tighten knob that maintains the finder’s collimation, even if the finder is removed between observing sessions. The bracket has two hand-adjust collimation screws that work in conjunction with a third spring-loaded post in the bracket. This makes collimation faster than the traditional three- or six-screw collimation methods used with conventional finder brackets.

Optical Quality
The heart of any telescope is its optics. GSO produces parabolic primary mirrors of very high quality. It is our firm opinion that GSO offers better mirrors in this price range. We guarantee a diffraction-limited performance, which essentially means that the performance is limited by observing conditions and the laws of physics.

Primary Mirror
8” (203mm) diameter, 1200mm focal length, f/5.9 focal ratio with surface accuracy of 1/12 wave. The mirror is made of B270 “water white” optical crown glass that is free of internal stress and striae. B270 glass is equivalent to BK7 in performance and optical quality. The thermal stability of B270 glass is generally better than the soda lime float glass used for the mirrors of most reflectors in this reasonable price range. The mirror is ground and polished under computer control for guaranteed diffraction limited performance, coated with 91% reflectivity aluminum, and overcoated with a protective layer of silicon dioxide (quartz) for long life.

Diagonal Mirror
62.5mm m.a. B270 “water white” optical crown glass, coated with 91% reflectivity aluminum and overcoated with a protective layer of silicon dioxide (quartz) for long life.

Primary Mirror Cell
Fully adjustable 3-point flotation system metal cell holds the primary mirror. The open frame of the cell allows the mirror to cool down to ambient temperatures quickly, so you can start observing sooner. Large hand-tighten color-coded push-pull collimation and collimation lock knobs make it easy to collimate the primary mirror with no tools required.

Diagonal Mirror
47mm m.a. B270 “water white” optical crown glass, coated with 91% reflectivity aluminum and overcoated with a protective layer of silicon dioxide (quartz) for long life.

Diagonal Mirror Support
Fully adjustable diagonal holder mounted on a low-diffraction four-vane thin spring steel spider.

Two Eyepieces
Fully multicoated Premium plossl eyepiece1.25"
Plossl 25mm 1.25" OD (48x)52° field
Plossl 9mm 1.25" OD(133x) 52° field

Primary Mirror Cooling Fan
A lightweight 4.7” diameter low-vibration cooling fan is built into the mirror cell to assure faster cool-down times. The battery-operated fan is powered by a battery pack that uses eight user-supplied AA batteries and plugs into a jack on the mirror cell frame.
 
GSO Crayford Focuser
The focuser is the most "visible" part of any telescope with the exception of the optics themselves. You touch the focuser all the time, the focuser is responsible for holding your eyepieces or camera in position and moving them precisely into focus in the first place. This way ultra-precise focus motion is possible for both visual and particularly photographical applications.

The features ::
The finest focuser GSO manufacturer has to offer. It is far superior to most classic rack-and-pinion focusers.
No image shift when focusing
Large load capacity: Up to approx.2.5kgs with a firm friction setting
2" compression ring
2" to 1.25" adaptor with compression ring and 2" filter thread

1. Smooth Focusing Action
The Crayford style focusing control makes achieving precise focus for visual observations and astrophotography a breeze and you will experience very smooth and precisely controlled focuser motion with zero backlash and zero image shift. 

2. High-Quality Construction and Features
CNC machined from aluminum and anodized black, this focuser comes with a base plate adapter to attach to reflector telescopes. The inner drawtube glides on 4 precision bearings and a roller shaft and provides. The inner barrel is baffled and painted a flat black to minimize reflections for maximum contrast.

The 2" focuser barrel features a brass compression ring so your eyepieces and other accessories will not be marred by the set-screw. Also included is a 1.25"-2" adapter with brass compression rings that is threaded to accept standard 2" filters.

The inner draw-tube barrel is anodized black and features a laser-etched scale.

3. Tension Adjustment and Focus-Lock
The focuser has two large thumbscrews on the underside. The thumbscrew on the telescope side can be used to lock the focuser, allowing the use of heavy accessories or cameras without fear or slippage or losing focus. The other thumbscrew on the eyepiece end can be used to adjust the tension of the focuser to achieve a focusing "feel" that you like. At the easiest (lightest) setting, the focuser moves extremely smoothly. At tighter settings, you can still use heavier accessories without sacrificing much of the smooth focuser action. GSO's rated load capacity for their Crayford focusers is about 3 kgs.

Eyepiece Tray
A standard equipment eyepiece tray attaches to the side of the scope’s altazimuth base. It has cutouts to hold one 2” eyepiece and three 1.25” eyepieces.

TELESCOPE SPECIFICATION

TELESCOPE SPECIFICATION
Country of Manufacturing	TAIWAN
Optical Design	Newtonian Reflecing Telescope
Primary Mirror	8 inch Parabolid Astronomical Mirror. Precisely figured Parabolic Mirror - diffraction limited / BK7 94% Enhanced Coating
Diameter	203mm
Focal Length	1200mm
Focal Ratio	F/6
Highest Practical Power	480
Faintest Steller Magnitude	14.2
Secondary mirror diameter	50 mm
Shadowing by the secondary mirror	25% linear
Adjustment aid	Center mark on the main mirror
Focuser	2 "-Crayford extension with ring clamp and adapter to 1.25"
Tube	Metal tube with reinforcement rings
Tube weight	13 kg
Tube length	1150 mm
Tube diameter :	230 mm
Rockerbox weight :	10.2 kg
Rockerbox dimensions :	Height 600 mm / diameter 500 mm
Storage :	Height with spring preload / azimuth with ball bearings
Resolving Power	0.57 Arc - Seconds.
Focuser diameter	2" Precission Crayford style focuser". With 1.25” eyepiece adapter.
Eyepiece Standard 1.25"	Premium Plossl 25mm (1.25") 52° field.
Eyepiece Standard 1.25"	Premium Plossl 9mm (1.25") 52° field.
Magnification with eyepiece	48x & 133.3x
Magnification with eyepiece	40x
Magnification with 2.5x barlow [ BUY SEPARATE ]	120x & 333.25x
Finder	8x50mm Fully multi-coated achromatic finder
Mount type	DOBSONIAN- wooden.
Mirror Cell	3 points mirror cell with cooling fan
Accessories Tray	2 inch Eyepieces tray
Mirror Stabiliser	Cooling fan for 'Thermal Equilibrium' Battery-operated primary mirror cooling fan
Total Height	52 inch
Tube Length	45.25 inch
Stand Height	27 inch
Base Diameter	20 inch
Shipping Weight approx	Tube : Net weight - 13 Kg / Gross weight: 13 Kg Stand: Net weight - 10.2 Kg / Gross weight: 12 Kg
Total weight of telescope	23.2 kg approx
Shipping Carton Dimension	Tube : 32 x 40 x 128 cm3 Stand: 15 x 64 x 64 cm3

 

COMPARISON GSO 8" Professional Dobsonian - vs - GSO 8" Nightwatch Dobsonian
	8" PROFESSIONAL	8" NIGHTWATCH
ACTUAL IMAGE
TOTAL PRICE	34500 + 18% GST	30000 + 18% GST
Country of Manufacturing - TAIWAN
Newtonian Reflecting Telescope	✓	✓
8 inch Parabolid 1/12 wave	✓	✓
diffraction limited / BK7	✓	✓
94% enhanced coating	✓	✓
Diameter - 203mm	✓	✓
Focal Length - 1200mm	✓	✓
Focal Ratio - F/ 6	✓	✓
Faintest Steller Mag - 14.2	✓	✓
Resolving Power - 0.57 Arc - Seconds	✓	✓
2" Precission Crayford Style Focuser	✓	✓
Dual-Speed 10:1 ratio Micor Focuser	✓
1.25” eyepiece adapter	✓	✓
Premium Widefield SP 30mm (2")	✓
Premium Plossl 25mm (1.25")		✓
Premium Plossl 9mm (1.25")	✓	✓
8x50mm Multi-coated Achromatic Finder	✓	✓
Dobsonian Wooden Base	✓	✓
Altitude Ball Bearings	✓
Altitude Clutch	✓
Azimuth Roller Bearing	✓
Tube Balancing System	✓
Cooling fan for 'Thermal Equilibrium'	✓	✓
Eyepiece Tray	✓	✓
Total Height	52 inch	52 inch
Tube Length	45.25 inch	45.25 inch
Stand Height	27 inch	27 inch
Base Diameter	20 inch	20 inch
Shipping Weight	Tube Net Weight 13Kg	Tube Net Weight 11Kg
	Gross weight 15 Kg	Gross weight 13 Kg
Shipping Carton Dimension	Tube 32 x 40 x 128 cm3	Tube 32 x 40 x 128 cm3
	Stand 14 x 60 x 70 cm3	Stand 15 x 64 x 64 cm3

WARNING

This device focuses a lot of light.
Looking directly at the SUN through this device can result in partial or complete loss of vision.
For observing the SUN, we recommend you buy a 'Solar Safety Film' for this Telescope.

Buy 1000 OAKS Solarite Safety Film

Instructions for use in ENGLISH

Download Instruction of GENERAL 203/1200 Dobsonian Reflector Telescope in .PDF format

Free Items [ Subject to Availability ]

• Collimination Tool (for Newtonian)

Suggested Accessories

246mm Cap Dia Solar Filter
₹ 3900

Galaxy Eyepiece
₹ 750

GSO 2X Achromatic BARLOW LENS
₹ 2100

GSO Azimuth Roller Bearing for DOBS
₹ 3900

Solar Filter for GSO 8" Telescopes
₹ 2400