beautypg.com

Getting started – Orion SHORTTUBE 80-T User Manual

Page 3

background image

3

Getting Started

The ShortTube 80-T comes nearly fully assembled from the
factory. The telescope’s optics have been installed and col-
limated, so you should not have to make any adjustments to
them. Open the box and inspect the contents to make sure
all of the items in the parts list are present.
Please keep the original shipping box. In the unlikely event
you should need to ship the telescope back to Orion for war-
ranty repair service, you should use the original packaging.
The box also makes a very good container for storing the
telescope when it is not in use.

Installing the Finder Scope
To place the finder scope in the finder scope bracket, first
unthread the two black nylon thumbscrews until the screw
ends are flush with the inside diameter of the bracket. Place
the O-ring that comes on the base of the bracket over the
body of the finder scope until it seats into the slot on the
middle of the finder scope. Slide the eyepiece end (nar-
row end) of the finder scope into the end of the bracket’s
cylinder opposite the adjustment screws while pulling the
chrome, spring-loaded tensioner on the bracket with your
fingers (Figure 2b.) Push the finder scope through the
bracket until the O-ring seats just inside the front opening
of the bracket’s cylinder. Now, release the tensioner and
tighten the two black nylon screws a couple of turns each to
secure the finder scope in place. Secure the bracket to the
dovetail mount on the optical tube with the knurled thumb-
screw provided.

Installing the Diagonal and Eyepiece
Insert the 45° diagonal into the focuser drawtube and secure
it with the knurled thumbscrew on the drawtube. Then insert
the 25mm Plössl eyepiece into the diagonal and secure it in
place with the thumbscrews on the diagonal. (Always loosen
the thumbscrews before rotating or removing the diagonal or
an eyepiece.)

Mounting the Telescope
The ShortTube 80-T can be mounted on any standard camera
tripod that has a 1⁄4"-20 stud. The stud threads into one of the
threaded holes on the bottom of the dovetail mounting plate
attached to the underside of the telescope optical tube.
You can also easily mount the telescope on altazimuth tele-
scope mounts like the Orion VersaGo. The dovetail mounting
plate on the bottom of the ShortTube 80-T connects to the
VersaGo mount’s dovetail holder. The dovetail holder has two
knobs to hold the dovetail mounting plate securely. Loosen
these two knobs accordingly and while grasping the telescope
firmly, place the dovetail mounting plate into the VersaGo's
dovetail holder. Tighten the two knobs to secure the telescope.
Alternatively, the telescope can be attached to any Orion
equatorial mount equipped with a dovetail holder. Follow the
directions above to couple the mounting plate to the equatorial
mount’s dovetail holder.
An equatorial mount is desirable for astronomical viewing
because it allows easy manual tracking of celestial objects
as the Earth rotates. Also, the setting circles on the mount
enable you to locate objects by their celestial coordinates
(right ascension and declination), which can be found in many
observing books and star atlases.
Focusing
The ShortTube 80-T is equipped with a precision rack-and-
pinion focuser. When you first look in the eyepiece, the
image you see may be fuzzy, or out of focus. If so, gently
turn one of the focusing wheels with your fingers until the
image becomes sharp. You will have to readjust the focus
when aiming at subjects of varying distances, or after
changing eyepieces. Make sure the focus thumbscrew is
loosened before focusing. After focusing, you can tighten it
to lock the telescope’s focus into place.

Figure 2b.

Inserting the finder scope into the finder scope

bracket.

Figure 2a.

The 6x26 correct-image finder scope and bracket.

Focus

lock-ring

Alignment thumbscrews

Tensioner