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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.

8" Nightwatch Dobsonian Telescope by GSO

₹29,700.00Price
  • 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
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