Orion CT80 User manual

Orion®CT80 Compact 80mm Refractor
Optical Tube Assembly
#09202
INSTRUCTION MANUAL
Congratulations on your purchase of an Orion CT80 Compact
Refractor! Your telescope has been designed with portability and
versatility in mind. Outt it with your favorite accessories and pop
it on the mount or tripod of your choice and you’ll be ready for a
superb observing experience. NOTE: If you are purchasing this
optical tube for use in the Awesome AutoGuider Package,
you’ll need to perform some disassembly in order to t the
tube into the rings. See below for detailed instructions.
The CT80 Compact Refractor comes fully assembled and optical-
ly collimated from the factory. The telescope’s optics have been
precisely collimated at the factory, so they should not require any
adjustments. Please keep the original shipping box. In the unlikely
event that you need to ship the telescope back to Orion for warran-
ty repair service, you should use the original packaging.
Refer to Figure 1 to become familiar with the telescope’s parts and
features.
Use as a Guide Scope
In order to use this optical tube in the rings that come with the
Awesome Autoguider Package, the nder scope bracket must be
removed from the optical tube. The tube will not t through the rings
otherwise.
Follow these steps to complete this procedure:
1. Locate and remove the three Focuser Assembly Screws to
remove the focuser (Figure 2). Be sure not to let the focuser
fall out of the tube when the screws are removed.
2. Carefully remove the focuser along with the silver trim ring
from the tube (Figure 3).
3. Locate the two Philips head screws in the nder scope base
(Figure 4). There are two nuts on the inside of the tube under
IN 597 09/17
Dew/glare shield scope base Drawtube
tension knob
Thumbscrew
Focus wheels
Focuser
Dovetail
mounting bar
Accessory
collar, 1.25"
WARNING: Never look directly at the Sun through
your telescope—even for an instant—without a
professionally made solar lter that completely
covers the front of the instrument, or permanent eye
damage could result. Young children should use this
telescope only with adult supervision.
Customer Support:
www.OrionTelescopes.com/contactus
Corporate Offices:
89 Hangar Way, Watsonville CA 95076 – USA
Copyright © 2017 Orion Telescopes & Binoculars
All Rights Reserved. No part of this product instruction or any of its contents may be reproduced, copied, modi-
ed or adapted, without the prior written consent of Orion Telescopes & Binoculars.
Providing Exceptional Consumer Optical Products Since 1975
®
Figure 1. Features and components of the CT80 Compact 80mm refractor

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both of these screws. With the tube horizontal on a table (so
the nuts don’t fall back towards the lens), loosen each screw
while pressing against the nut inside the tube with a ngertip.
You may need a small crescent wrench if the nuts are tight
against the tube wall. Remove the nuts from inside the tube,
and pull off the nder scope base along with the screws
(Figure 5).
Figure 2. Focuser assembly screws
Figure 3. Remove the focuser
Figure 4. Finder bracket screws
Figure 5. Finder bracket removal
Finder bracket
must be removed
Focuser assembly screws

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4. Reattach the screws and nuts to the open holes so that
no dust gets inside the tube and tighten with a screwdriver
(Figure 6), then reinstall the focuser, making sure the focus
knobs are back in the same orientation.
5. Figure 7 shows the reassembled optical tube sitting in the
guide ring setup.
Figure 6. Reinstall the screws, nuts, and focuser
Figure 7. Finished assembly in guide rings
Care & Maintenance
Give your telescope reasonable care and it will last a lifetime. When
not in use, keep its dust cover on as well as the small plastic plug
on the focuser drawtube. Store it indoors or in a dry garage. Do
not leave the telescope outside except when using it. If a scratch
appears on the tube, it will not harm the telescope. Smudges on the
tube can be wiped off with standard household cleaners.
Dew
When you are ready to pack up your telescope at the end of the
night, avoid immediately storing it if you encountered heavy dew
and the telescope is damp. Instead, bring the telescope inside and
allow the moisture on the telescope to evaporate. If dew forms on
the objective lens, then leave the dust cover off of the telescope
until all the moisture has evaporated. Once the telescope has com-
pletely dried out, place it back in its case.
Cleaning Optical Surfaces
In general, your telescope will only need to be cleaned on a very
minimal basis. Dust particles on the objective lens do not affect the
optical quality of your refractor. Loose dust can simply be blown
off with air, using a compressed air can or photographer’s blow-
er bulb. Any remaining dust is best left alone, unless the build up
is extreme. Fingerprints and water marks should be cleaned from
your telescope’s objective lens. Any quality optical lens tissue and
cleaning uid specically designed for multi-coated optics can be
used to clean the telescope’s objective lens as well as the lenses of
your eyepieces and nder scope. Never use regular glass cleaner,
or cleaning uid designed for eyeglasses.
Before cleaning with uid and tissue, however, blow any loose par-
ticles off the lens with a blower bulb or compressed air, or lightly
brush the lens with a soft camel hair brush. Apply some cleaning
uid to a tissue, never directly on the optics. Wipe the lens gently
in a circular motion, then remove any excess uid with a fresh lens
tissue. Oily ngerprints and smudges may be removed using this
method. Use caution; rubbing too hard may scratch the lens! Clean
only a small area at a time, using a fresh lens tissue on each area.
Never reuse tissues.
Specifications
Optical tube: Seamless luminum
Optics design: Achromatic (doublet)
Lens glass: Crown and int
Aperture: 80mm
Focal length: 400mm
F-ratio: 5.0
Lens coatings: Fully coated (all air-to-glass
surfaces MgF2 coated)
Tube baffle: Yes
Tube length: 14-3/4” / 377mm
Dew shield outer diameter: 4-1/8” / 105mm
Weight: 2 lbs. 4 oz. / 0.94 kg
Focuser: 25” rack and pinion
Drawtube travel: 2-7/8” / 74mm
Focus lock: Yes
Mounting bar: Aluminum, Vixen style, 3-1/8”
length

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One-Year Limited Warranty
This Orion product is warranted against defects in materials or workmanship for a period of one year from the date of purchase.
This warranty is for the benet of the original retail purchaser only. During this warranty period Orion Telescopes & Binoculars
will repair or replace, at Orion’s option, any warranted instrument that proves to be defective, provided it is returned postage paid.
Proof of purchase (such as a copy of the original receipt) is required. This warranty is only valid in the country of purchase.
This warranty does not apply if, in Orion’s judgment, the instrument has been abused, mishandled, or modied, nor does it apply
to normal wear and tear. This warranty gives you specic legal rights. It is not intended to remove or restrict your other legal rights
under applicable local consumer law; your state or national statutory consumer rights governing the sale of consumer goods
remain fully applicable.
For further warranty information, please visit www.OrionTelescopes.com/warranty.
Orion®Telescopes & Binoculars
Corporate Offices: 89 Hangar Way, Watsonville CA 95076 - USA
Customer Support: www.OrionTelescopes.com/contactus
Copyright © 2017 Orion Telescopes & Binoculars
All Rights Reserved. No part of this product instruction or any of its contents may be reproduced, copied, modified or adapted, without the prior
written consent of Orion Telescopes & Binoculars.