Thinking About a New Scope? Think Big!
Accessories
Argo Navis™ Digital Setting Circles
with Super Res 10K encoders
The Argo Navis™ Digital Telescope Computer (DTC) brings not only accurate positioning information to your telescope but also provides an enormous detailed database of tens of thousands of celestial objects. Stars, asterisms, galaxies, globular clusters, open clusters, planetary nebula, nebula, planets, asteroids, comets, earth-orbiting satellites and more.
Magnitudes, surface brightnesses, object sizes, common names, stellar classifications, stellar luminosity classes, double star separations, Hubble galaxy morphologies, constellation, detailed parameters of planets, comets, asteroids, satellites and a wealth of other information is available at your fingertips with a simple spin of the dial.
Instructions for self installation: 12.5, 15, 18, and 20 inch - 25 and 20 inch
$895.00 installed
See the Argo Navis™ page for more details
ServoCAT Goto Drive System
Servo Drive Computerized Astronomical Telescope
The new full featured ServoCAT will power your Obsession telescope to new horizons - and zeniths! Now you can enjoy your Obsession telescope to it's fullest potential. Coupled with the "Argo Navis digital setting circles" your scope will be tracking with ease and provide full GoTo ability. Read the features below to learn why the ServoCAT is taking over the motorized telescope market in large aperture dobs.
The ServoCAT GoTo drive with Argo Navis digital setting circles and Super resolution 10K count encoders complete system installed is:
$2,995 on the 12.5 inch Obsession
$3,195 on the 15, 18, or 20 inch Obsessions
$3,295 on the 22 and 25 inch Obsessions
See the ServoCAT page for more details
Focusers
Choose from four great focusers. The JMI EV3 comes standard on all Classic Obsessions. Or upgrade to the EV1, or EV1 with motofocus, or the awesome Feathertouch by Starlight Instruments. (Feathertouch comes standard on all UCs)
JMI EV3
Comes standard
on all Classic Obsessions
JMI EV1
$195 Upgrade
JMI EV1
with Motofocus
$295 Upgrade
Feathertouch
by Starlight Instruments
$395 Upgrade
(standard on all UCs)
See the Focuser Options page for more details
Super Res 10K resolution encoders
With mounting hardware / wiring harness only installed (you have computer already):
$375

Ethos eyepieces by Televue
6mm, 8mm, 13mm, 17mm, and 21mm
These amazing eyepieces have a 100 degree apparent field of view. You might have to turn your head to see from one side to the other as your eyeball can't move that far!
We are often asked "What eyepieces should I use"? TeleVue eyepieces are simply the best for fast reflecting telescopes like the Obsession.
We are also a Televue dealer and offer OEM discount pricing on all eyepieces, filters, barlows and more.
Email for price and delivery info.
Barlow-Laser Collimator 2" barrel
Highly recommended. Includes 2" magnetic barlow lens and removable mask for the new barlowed laser collimating technique. Great visual aid, and no better way to accurately align fast Newtonians. Has recessed switch.
See: Collimation Instructions & Barlowed Laser Technique
$160
Finders
Dew heater for secondary mirror
Sizes available to fit all apertures
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. Gently warms the secondary at 2-4 watts when on full. Six evenly spaced contact points for optimal thermal distribution. Uses a 9v battery (smoke alarm battery) mounted at the holder, eliminating the need for wires across the spider. No more heat ropes! On/off sensor and LED indicator included.
See: Dew heater installation instructions
$75
Ripstop Nylon light shroud
Made from 100% ripstop nylon tent fabric - not cheap cotton T-shirt fabric like most others.
Includes custom Nylon stuff sack.
$169 for 12.5" Classic
$179 for 15" Classic and 15" UC
$189 for 18" Classic and 18" UC
$199 for 20" Classic
$219 for 22" UC
$229 for 25" Classic
Counterweight kit
Recommended if you intend to use heavy barlow/eyepiece combinations, a Paracorr coma corrector, a traditional finderscope, or the Argo Navis digital setting circles.
$35
(you supply the lead shot or sand)
Custom Obsession Telescopes decals for your trailer or vehicle
Black graphic on white background with a thin black / white border, and includes your scope aperture in the lower right corner. Or get one without the scope aperture.
Made for the side walls or rear door of your scope trailer. Or apply them to the windows of your vehicle, or any surface you want to dress up with our cool looking logo.
These attractive, self adhesive decals are made of durable vinyl with a glossy vehicle overlam that will last many years.
4" x 5" $3.00 each
8" x 10" $6.00 each
14" x 18" $15.00 each
19" x 24" $25.00 each
28" x 36" $32.00 each
38" x 48" $48.00 each
48" x 60" $78.00 each
Application instructions included.
For more info, or to order,
contact Roger Greenwood at:
roger@astrocrumb.com
www.astrocrumb.com![]()
(also home of the FilterSlide)
When ordering, be sure to indicate the aperture for the lower right corner. Or get them without the aperture.
third-party accessories
IZOD polo shirt
Available from
Dark Skies Apparel![]()
High quality IZOD silk washed pique cotton polo shirt. It has the Obsession logo embroidered on the left chest and your telescope size & type embroidered on the left sleeve.





