8″ Nightwatch Dobsonian Telescope by GSO

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!

Please Download INSTRUCTION MANUAL Physical Copies of the manual will not be given.

8×50 Finderscope
Powerful 8×50 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.

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