Used 15" Obsession Classic Dobsonian

  • Sale
  • $3,750.00
  • Regular price $10,385.00


Contact use for ordering information.

Condition: This is a used 15" Obsession Dobsonian in excellent condition.  The previous owner took excellent care of his equipment and it shows.  You've heard of the quality that is an Obsession scope, now come see it for yourself. 

This scope includes both the Argo Navis digital setting circles as well as the ServoCAT goto drive/tracking system.  The scope with these accessories comes to over TEN THOUSAND DOLLARS.  This scope is a screaming deal.



Medium Aperture, keep your feet on the ground!

Now everyone can own a piece of the dream.

The Obsession 15 has the same quality and award winning design as our other telescopes at a really great price.

Four times the light gathering power of an 8 inch scope so you get much bigger and brighter images.

With an Obsession 15 you can really see the universe.

Easy to set up and use, the eyepiece height is always less than 5 1/2 feet off the ground. Most observers won't even need to use a ladder!

Wheelbarrow handles included at no extra charge.

4 times the light gathering power of an 8 inch Schmidt-Cassegrain Obsession
Limiting stellar magnitude: 15.5 14.0
Rayleigh Resolution Limit: 0.36
arc seconds
arc seconds
Contrast limit:
(minimum diameter before a
nebular object fades from view)
arc minutes
arc minutes



15" Specifications:

Metric info shown in italics

Primary Mirror:

  • 15" - 381 mm OMI 2 inch thick mirror
  • Fused silica glass standard on all 15" Classic primary mirrors.
  • 96% reflectivity
  • Enhanced Aluminum Coating and Dielectric Overcoat (a supreme coating)
  • Center marked for precise collimation
  • plus Interferometry certification

see Optics page for more info

Secondary Mirror:

  • Pre-installed
  • 2.6" - 66 mm United Lens 1/10 wave or better
  • Interferogram included
  • 96% reflectivity at 550 nm
  • Super enhanced Brilliant-Diamond non-fading multi-dielectric coating

see Optics page for more info

Focal Length:

  • 68" (± 2") - 1727 mm (± 50 mm)

Eyepiece Height at Zenith:

  • (approximately) 66" - 167 cm

Mirror Cell:

  • 9-point

Truss Pole:

  • Length: 45" (± 2") - 114 cm (± 5 cm)
  • Diameter: 1.25" - 32 mm
  • Wall Thickness: 0.035" - 0.9 mm

Upper Assembly:

  • Diameter: 19" - 48 cm
  • Height: 10" - 25 cm
  • Weight: 8 lbs. - 3.6 kg

Lower Assembly:

  • A= 25" - 63 cm | B= 23" - 58 cm | C= 19" - 48 cm | D= 21" - 53 cm

see diagram

Mirror Box weight:

  • The heaviest component (what you don't lift): 60 lbs - 27 kg
  • Weight at Handles: (what you lift at Wheelbarrow handles): 9 lbs - 4 kg

Standard Features and Accessories:

Wheelbarrow handles

Comes standard on all Obsessions 12.5" through 25" at no extra charge.

Primary Mirror Coating

Enhanced Aluminum - 96% reflectivity, with dielectric overcoat (a supreme coating) standard on all primary mirrors. See Optics page for more info.

Secondary Mirror Coating

An Obsession exclusive - Super enhanced Brilliant-Diamond is standard on all Obsession secondary mirrors. This premium multi-dielectric coating has 96% reflectivity at 550 nm. The ultimate coating for the deep sky obsessed. This coating is standard on all Obsession secondaries at no extra charge. Brilliant-Diamond is just one of the reasons Obsessions out perform all others.

With 96% enhanced on the primary and our standard 96% Brilliant Diamond secondary, the optical system is equivalent to an extra 2" of aperture!

12 volt cooling fan

telescope mirror cooling fan

12 volt cooling fan comes standard on all Classic and Ultra Compact scopes.

Fused quartz

15” Obsessions use fused quartz for the primary mirror glass.

more info

Argo Navis digital setting circles

with ultra res 32K encoders

more info

ServoCAT Goto Drive System

more info

    SKU: U2111-15OBSESSION