Sky-Watcher Stargate 450P SynScan 18" Truss Dobsonian


Availability: More on the way

The Sky-Watcher Stargate dobsonians will allow you to see things that you never thought possible.

Our Product #: S11900
Sky-Watcher Product #: S11900
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Product Description

If you want to observed Deep Space objects, this should be the scope for you.  The 18" primary mirror is a light gathering tour de force.  Throw in a clear sky  and you have a truly stunning portable observatory.  The 18" Stargate Truss Tube Dobsonian will start to bring in all those hard to find objects in the sky and even introduce some whisps of color.  Looking through a truly large telescope is like seeing the sky for the first time.
If you are an average astronomer, then you more than likely use an 8" scope of some sort.  Well, the 18" gathers 500% more light taking your observation to another level.  Now there is a trade-off for all this size, and that is the weight of the instrument.  As with all truss dobsonians, the telescope breaks down for ease transportation.  Be forewarned, you will still have to lug around a few pieces with the heaviest weighing in at 66 pounds.  Once you get it all moved and assembled you are ready for a night of exploration and tranquility.  
The fused conical parabolic mirrors allow for a lighter mirror that will cool faster getting you oberving more quickly while saving your back.  Once you get your scope all set up you will notice the eyepiece is not too far off the ground as it sits right at 74.5" when pointing at the zenith. 
Optical Design


Primary Aperture (mm)

458mm (18”)

Secondary Diameter (mm)

120mm minor axis

Secondary Obstruction by Area


Mirror Coatings

94% Aluminum

Glass Type


Focal Length (mm)


Focal Ratio


Light Gathering (compared to next size down)

Captures 27% more light than a 16” telescope

Zenith Eyepiece Height


Rayleigh Limit


Dawes Limit


Limiting Magnitude


Minimum Magnification


Maximum Magnification




Object Database


Dual Encoders



2″ Dual Speed Crayford

Included Eyepieces

28mm LET eyepiece and 10mm eyepiece

Included Finder


Other Included Items

2.3lbs counter weights (3), Shroud, Truss clamps

Upper Cage Weight


Truss Pole Weight

2.6lbs each. 16lbs total

Mirror Box Weight


Dobsonian Base Weight


Fully Assembled Weight (with weights)


Tech Details

Aperture 18"
Focal Length 1900mm
Focal Ratio f/4.1
Heaviest Single Component 62
Motorized Controls No
Weight 129 pounds
Supplied Eyepiece 28mm LET eyepiece and 10mm eyepiece
Telescope Type Reflector
View Finder 9x50
Visual Limiting Magnitude 15.9


Review by:
This brings you the best of both worlds. Portability and quality. Collimation is a sinch and setup is very easy. I absolutely love this scope and will cherish it for many years to come. (Posted on 1/2/2019)
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