Sky Watcher 18" Stargate Truss-Tube Dobsonian

  • Aperture: 18-Inch
  • Focal Length: 1900 mm
  • Focal Ratio: f/4.1
  • Focuser: Dual Speed 2-Inch Crayford
  • Best suited for: High-end visual observation


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  • Regular price $5,999.00

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Sky Watcher 18" Stargate Truss-Tube Dobsonian

Stargate 450P 458 mm (18-Inch) Aperture Truss Dobsonian Telescope:

Sky-Watcher has opened a portal to the stars with the new Stargate 18-Inch Truss-Tube Dobsonian telescope. This telescope designed for immense light gathering power and ease of use, and is sure to deliver on both fronts for the most discerning of visual astronomers. With a total light gathering power of 4266x and a maximum useful magnification of 914x, you will find that the Sky-Watcher Stargate 18-Inch Dobsonian makes it easy and enjoyable to scour planetary and deep sky visual targets for the most refined and subtle of details. Sky-Watcher approximates this telescope to have a roughly thirty minute setup time due to how easily assembled it is; a factor that, when combined with it's low weight of 110-pounds compared to its size class, makes this a great scope for taking out to local star parties or dark sites despite its immense power and size; it's simply designed in that efficient of a method.

And of course, it's not just raw power and convenience that Sky-Watcher prioritized when designing and making the Stargate 18-Inch. They also made sure to include a primary parabolic mirror design that eliminates the spherical aberrations that are otherwise inherent in faster focal length reflectors. These mirrors are designed to bring all of the light your telescope has gathered to a single focal point and ensure sharp, high contrast, high detail images. Every optical mirror in the Stargate, including that primary mirror, is heavily multi-coated with high quality Silicon Dioxide coatings that ensure optimal durability and performance.

The Zenith Eyepiece Height for this system is 74.5-inches. It gathers and captures 27-percent more light than a 16-inch telescope. The Mirror coatings are 94-percent Aluminum. The Secondary Diameter is 120 mm minor axis.


Major Component Weights:

  • Dobsonian Base: 40-pounds
  • Mirror Box: 62-pounds
  • Truss Poles: 2.6-pounds each, 16-pounds total
  • Upper Cage: 11-pounds
  • Counterweights: 2.3-pounds each, (3) 6.9-pounds total

When fully assembled without weights this item weighs 129-pounds.



Aperture457 mm (18")
Dawes Limit0.25
Focal Length1900 mm
Focal Ratiof/4.1
Free ShippingYes
Glass TypeBorosilicate
Limiting Magnitude15.9
Maximum Magnification902x
Minimum Magnification65x
Optical DesignDobsonian
Secondary Obstruction7%



  • Sky-Watcher 18-Inch Stargate Dobsonian
  • 2-Inch Dual Speed Crayford Focuser with 1.25-inch and 2-inch Extension Tubes
  • 2-Inch 28 mm LET Eyepiece
  • 2-Inch 10 mm Eyepiece
  • 9 x 50 Straight-Through Finderscope
  • Cast Metal Rocker and Base with Teflon Bearings
  • 3 Counterweights, 2.3-pounds each
  • Clamps and Shroud