Fused conical primary mirror
Cellular secondary mirror
Dual speed 2” Crayford focuser
Two section truss poles (compact transport)
Minimalist, all metal construction
Fast f/3.95 optics for short eyepiece heights
20” provides 56% more light than a 16” telescope
94% reflectivity coatings


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Our superior optics just got better

Stargate’s feature Sky-Watcher’s exclusive fused conical parabolic mirrors. The fused design allows for thinner mirror construction that provides faster cooling and lighter weight.

Combined with the cast cellular secondary mirror and Sky-Watcher’s exclusive 94% reflectivity coatings, Stargate delivers bright, detailed views of your favorite deep sky objects. The 18 inch model captures 27% more light than our 16 inch, while the 20 inch (a full half meter of aperture) boasts a monster 56% more light gathering power.

Solid foundations, easy assembly

The minimalist all-metal structure of the Stargate produces a sturdy and stable platform while maintaining a convenient and compact footprint. The truss-tubes break down to a very manageable 36 inch length for easy transport. Azimuth and altitude bearings are steel and Teflon for smooth, steady movement.

Setting up a Stargate is a simple procedure, taking only about 20 minutes. Spring loaded truss anchor points are clearly labeled to eliminate any frustration or confusion. Adjustable feet make leveling a snap.

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Optical Info
Optical Design: Newtonian
Mirror Coatings: 94% Aluminum
Glass Type: Borosilicate
Primary Aperture (mm): 508
F/Ratio: 3.93
Focal Length (mm): 2000
Secondary Diameter: 134mm
Secondary Obstruction (by diameter): 26%
Secondary Obstruction by Area: 7%

Observational Info
Dawes Limit: 0.23
Rayleigh Limit: 0.28
Limiting Mag.: 16
Minimum Magnification: 72
Maximum Magnification: 1000
Light Gathering (compared to next size down): 23%
General Info:
Focuser: 2" Dual Speed Crayford
Zenith Eyepiece Height: 79"
Dob Base Weight: 40 lbs
Upper Cage Weight: 12 lbs
Truss Pole Weight: 2.6 lbs each. 16 lbs total
Mirror Box Weight: 70 lbs
Full Assembled Weight (with weights): 138 lbs

Included Finder: 9x50 Finder
Included Diagonal: No
Included Eyepieces: 28 LET/10mm/Coll.
Magnification w/ Included Eyepieces: 71x/200x
Included Case: No
Corrector: No
Other Included Accessories: 2.3 lb counter weights (3), Shroud, Truss clamps

Stargate 500P
9x50 finder
28mm LET eyepiece
10mm eyepiece
Coll. eyepiece
3x 2.3 lb counterweight
Truss clamps

Stargate 450P Manual