Obsession Telescopes
Thinking About a New Scope?
Think BIGNewsWhy Buy an Obsession?Big Dob ChecklistObsession OpticsFrom The ObsessedReviewsPublicationsObsession FirstsM13 Comparison"The Dobsonian Telescope" by Kriege & Berry



Loading the 15" into Subaru wagon with the wheelbarrow handles


or just pick it up and skip the ramps!


Occultation of Jupiter taken by Becky Correti and Bill Williams with web cam and 15" Obsession. This photo series also appears in the April issue of Sky and Telescope on page 132.


Saturn with 15" Obsession taken by Alberto Fernando in Portugal.


Mars with 15" Obsession and ServoCAT taken by Alberto Fernando in Portugal.


Helix Nebulae taken by Pierre Schmidt and Eduard von Bergen in Austria with 15" Obsession on equatorial platform and Canon EOS 10D digital camera. The Helix is the closest planetary nebulae to earth and hence one of the largest.


M27, the Dumbell Nebulae in Vulpecula taken by Pierre Schmidt and Eduard von Bergenin in Austria with 15" Obsession on equatorial platform and Canon EOS 10D digital camera.


DVD
Free Obsession DVD product Video
To obtain a hard copy of Obsession literature including our 120 minute product video, e-mail your POSTAL address, or fill out this form and we'll mail it to you at no charge (World-wide).

The video is great for determining which aperture is best for you.


Telescopes
| 12.5" | 15" | 15" UC | 18" | 18" UC | 20" | 25" |

Home > Telescopes > 15" Obsession



Medium Aperture,
keep your feet on the ground!

 15" - f/4.5

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.

See what obsessed owners have to say about the 15" Obsession


M13 CCD image
by Doug Askew
with 15" Obsession.
M51 CCD image
by Doug Askew
with 15" Obsession.
NGC 2903 CCD image
by Doug Askew
with 15" Obsession.

View Specifications Table for all Obsession Telescopes
English version | Metric version
Download PDF

COMPARISON
4 times the light gathering power
of an 8 inch Schmidt-Cassegrain
 Obsession
15"		 Typical
8"
Limiting stellar magnitude: 15.5 14.0
Rayleigh Resolution Limit: 0.36
arc seconds		 0.68
arc seconds
Contrast limit:
(minimum diameter before a
nebular object fades from view)		 5.7
arc minutes		 11.0
arc minutes
M13 Comparison

Expand all | Collapse all
15" Specifications: click to expand / collapse


Primary Mirror:

  • 15" - 381 mm OMI 2 inch thick mirror
  • 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:

  • 2.6" - 66 mm United Lens
  • 98% 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)

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: (see diagram):
A= 25" - 63 cm | B= 23" - 58 cm | C= 19" - 48 cm | D= 21" - 53 cm

Total Weight: (what you don't lift): 60 lbs - 27 kg
Weight at Handles: (what you do lift at Wheelbarrow handles): 9 lbs - 4 kg

Eyepiece Height at Zenith: (approximately) 5.5 feet - 167 cm

COMPARISON
4 times the light gathering power
of an 8 inch Schmidt-Cassegrain
 Obsession
15"		 Typical
8"
Limiting stellar magnitude: 15.5 14.0
Rayleigh Resolution Limit: 0.36
arc seconds		 0.68
arc seconds
Contrast limit:
(minimum diameter before a
nebular object fades from view)		 5.7
arc minutes		 11.0
arc minutes



Mirror Options: click to expand / collapse

see the Optics page for more info

Obsessions are built with premium diffraction limited optics from Galaxy and OMI (Optical Mechanics Inc.).

Only OMI supplies mirrors for our 15".

Obsessions are also available without optics if you already have your mirrors. Call, fax, or email for price and delivery.


Standard Options and Accessories click to expand / collapse

  • Choose from four great focusers
    The JMI EV3 comes standard on all Obsessions. Or upgrade to the EV1, or EV1 with motofocus, or the awesome Feathertouch by Starlight Instruments. See the Focuser Options page for more focuser options

  • Wheel Barrow handles
    Comes standard on all Obsessions 15" through 25" at no extra charge.
    Optional on the 12.5".

  • Primary Mirror Coating
    Enhanced Aluminum - 96% reflectivity, with dielectric overcoat (a supreme coating) standard on all primary mirrors.

  • Secondary Mirror Coating
    An Obsession exclusive - Super enhanced Brilliant-Diamond is standard on all Obsession secondary mirrors. This premium multi-dielectric coating has 98% 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 98% Brilliant Diamond secondary, the optical system is equivalent to an extra 2" of aperture!


Optional Accessories: click to expand / collapse

See the Accessories page for more info on these items

  • Telrad

  • Ripstop Nylon light shroud.

  • Barlow-Laser Collimator 2" barrel. Highly recommended. Includes 2" magnetic barlow lens and mask for the new barlowed laser collimating technique. Great visual aid and no better way to accurately align fast Newtonians. learn how

  • Argo Navis digital setting circles with super res 10K encoders. more info

  • ServoCAT Goto Drive System. more info

  • Counterweight kit - (you supply the lead shot or sand) Recommended if you intend to use heavy barlow/eyepiece combinations, a Paracorr coma corrector, a traditional finderscope, or the Argo Navis digital setting circles.

  • Dew heater for secondary mirror - Secondary mirror heating system automatically senses the air temperature and the mirror temperature, then maintains the secondary at a preset (adjustable) temperature above the ambient air temperature to prevent dewing or icing. more info


Ordering Information: click to expand / collapse

A Deposit is required to place an order ($1,600 for 15").

Mail the deposit to:
Obsession Telescopes
PO Box 804
Lake Mills, WI 53551
USA

You can e-mail your order, or mail it with the deposit.

  • With your order, please list any options and/or accessories you want, your mailing address, e-mail address if any, and phone number(s).
  • After we receive it, we will send you an order confirmation letter.
  • Delivery is usually 1 to 2 months from time of order.
  • Please e-mail for current delivery times.
  • Balance due prior to shipment.
  • Prices do not include shipping and crating. We ship throughout the world via UPS.
  • Any questions, please call or e-mail.
  • NOTE 10% order cancelation charge.

Need more information?
E-mail your postal address and we'll send you the Obsession brochure and video at no charge.


^ Return to TOP ^ | 12.5" | 15" | 15" UC | 18" | 18" UC | 20" | 25" |