ORION TELESCOPES & BINOCULARS ShortTube 4.5 EQ 9849 Instruction Manual

IN 187 Rev. A 05/02

Providing Exceptional Consumer Optical Products Since 1975

Customer Support [phone]
E-mail: [e-mail]

Corporate Offices [phone]
P.O. Box 1815, Santa Cruz, CA 95061

INSTRUCTION MANUAL

Orion

®

ShortTube

™

4.5" EQ

#9849 Equatorial Reflecting Telescope

2

Figure 1. The ShortTube 4.5 EQ.

EZ Finder II

Focuser

Eyepiece

Tube rings

EZ Finder II bracket

Bracket securing thumbnuts

Right ascension setting circle

Right ascension

slow motion control cable

Latitude adjustment T-bolt

Tripod leg

Leg lock knob

Declination slow-motion
control cable

Declination lock knob
Declination setting circle
Counterweight shaft
Counterweight
Counterweight lock knob

Latitude lock T-bolt
(not shown)

Azimuth lock knob

Accessory tray bracket
Accessory tray

Tripod leg

3

Table of Contents

1. Unpacking . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Parts List . . . . . . . . . . . . . . . . . . . . . . . . 3

3. Assembly . . . . . . . . . . . . . . . . . . . . . . . . 3

4. Getting Started . . . . . . . . . . . . . . . . . . . . 5

5. Setting Up and Using the

Equatorial Mount . . . . . . . . . . . . . . . . . . . 7

6. Collimating the Optics

(Aligning the Mirrors) . . . . . . . . . . . . . . . . 9

7. Astronomical Observing . . . . . . . . . . . . 11

8. Care and Maintenance . . . . . . . . . . . . . 14

9. Specifications . . . . . . . . . . . . . . . . . . . . 14

1. Unpacking

The entire telescope system will arrive in one box.Be careful
unpacking the box.We recommend keeping the original ship­ping containers. In the event that the telescope needs to be
shipped to another location, or returned to Orion for warranty
repair, having the proper shipping containers will help ensure
that your telescope will survive the journey intact.

Make sure all the parts in the Parts List are present. Be sure
to check boxes carefully, as some parts are small. If anything
appears to be missing or broken, immediately call Orion
Customer Support (800-676-1343) for assistance.

2. Parts List

Qty. Description

1 Optical tube assembly
1 Optical tube dust cap
2 Tube mounting rings
1 Equatorial mount
1 EZ Finder II reflex sight with mounting bracket
2 Slow-motion control cables
3 Tripod legs with attached accessory tray bracket
3 Leg lock knobs
3 Tr ipod attachment screws with wing nuts and

washers
1 Counterweight shaft
1 Counterweight
1 Tripod accessory tray
1 25mm Explorer II eyepiece
1 10mm Explorer II eyepiece
1 Collimation cap

3. Assembly

Assembling the telescope for the first time should take about
30 minutes.You will need a Phillips head screwdriver in addi­tion to the tools provided. All screws should be tightened
securely to eliminate flexing and wobbling, but be careful not
to over-tighten or the threads may strip. Refer to Figures 1
and 2 during the assembly process.

During assembly (and anytime, for that matter), Do not touch
the surfaces of the telescope mirrors or the lenses of the EZ
Finder II or eyepieces with your fingers.The optical surfaces
have delicate coatings on them that can easily be damaged
if touched inappropriately. Never remove any lens assembly
from its housing for any reason, or the product warranty and
return policy will be voided.

Congratulations on your purchase of a quality Orion telescope. Your new ShortTube 4.5 is a terrific

starter instrument for exploring the exotic wonders of the night sky. Designed to be compact and easy
to use, this telescope will provide many hours of enjoyment for the whole family.

If you have never owned a telescope before, we would like to welcome you to amateur astronomy. Take
some time to familiarize yourself with the night sky. Learn to recognize the patterns of stars in the major
constellations. With a little practice, a little patience, and a reasonably dark sky away from city lights,
you’ll find your telescope to be a never-ending source of wonder, exploration, and relaxation.

These instructions will help you set up, properly use and care for your telescope. Please read them
over thoroughly before getting started.

WARNING: Never look directly at the Sun

through your telescope—even for an instant—
without a professionally made solar filter that
completely covers the front of the instrument, or
permanent eye damage could result.Young
children should use this telescope only with
adult supervision.

4

1. Lay the equatorial mount on its side. Attach the tripod
legs one at a time to the mount using the tripod attach­ment screws.Line up the holes in the top of the tripod leg
with the holes in the base of the mount, and install a
screw so it passes through the leg and the mount with
one washer on both sides of the tripod leg. Tighten the
wingnuts only finger-tight, for now.

2. Install and tighten the leg lock knobs on the bottom
braces of the tripod legs. For now, keep the legs at their
shortest (fully retracted) length; you can extend them to a
more desirable length later, after the tripod is completely
assembled.

3. Stand the tripod and mount upright and spread the tripod
legs apart as far as they will go, until the accessory tray
bracket is taut. Connect the accessor y tray to the acces­sory tray bracket with the three wing screws already
installed in the tray. Do this by pushing the wing screws
up through the holes in the accessory tray bracket and
threading them into the holes in the accessory tray.

4. Next, tighten the screws at the tops of the tripod legs, so
the legs are securely fastened to the mount. Use the
Phillips head screwdriver and your fingers to do this.

5. Orient the equatorial mount as it appears in Figure 2, at a
latitude of about 40°, i.e., so the pointer next to the lati­tude scale is pointing to the mark at “40.” To do this,
loosen the latitude lock T-bolt, and tur n the latitude
adjustment T-bolt until the pointer and the “40” line up.
Then retighten the latitude lock T-bolt. The declination
(Dec.) and right ascension (R.A.) axes may need re-posi­tioning (rotation) as well. Be sure to loosen the R.A. and
Dec. lock knobs before doing this. Retighten the R.A. and
Dec. lock knobs once the equatorial mount is properly
oriented.

6. Thread the counterweight shaft into the equatorial mount
at the base of the declination axis until tight.

7. Remove the screw and washer on the bottom of the
counterweight shaft and slide the counterweight onto the
shaft. Make sure the counterweight lock knob is ade­quately loosened to allow the counterweight shaft to pass
through the hole. Position the counterweight about
halfway up the shaft and tighten the lock knob. Replace
the screw and washer on the end of the shaft.

8. Attach the two tube rings to the equatorial head using the
hex head screws that come installed in the rings.Remove
the screws, then push them, with the washers still
attached, up through the holes in the tube ring mounting
plate (on the top of the equatorial mount) and rethread
them into the bottom of the tube rings.Tighten the screws
securely with the included wrench. Open the tube rings
by loosening the knurled ring clamps.

9. Attach the two slow-motion cables to the R.A. and Dec.
worm gear shafts of the equatorial mount by positioning
the thumbscrew on the end of the cable over the indented
slot on the worm gear shaft and then tightening the
thumbscrew. We recommend that the shorter cable be
used on the R.A. wor m gear shaft and the longer cable
on the Dec. worm gear shaft.

10.Loosen and remove the EZ Finder II bracket securing
thumbnuts from the optical tube assembly. Place the
holes in the bottom of the EZ Finder II bracket over the
two threaded shafts coming out of the optical tube.
Replace the thumbnuts to secure the bracket to the opti­cal tube.Refer to Figure 1 for the proper orientation of the
bracket.

11. Attach the EZ Finder II to its mounting bracket by loosen­ing the two thumbscrews on the EZ Finder II and sliding it

Figure 2. The ShortTube 4.5’s equatorial mount.

Right ascension
lock knob

Right ascension
setting circle

Latitude scale
Latitude lock T-bolt
Latitude adjustment

T-bolt

Declination lock knob

Declination

setting circle

Azimuth lock knob

5

onto the bracket. Retighten the thumbscrews to secure
the EZ Finder II in place.

12.Inser t the 25mm Explorer II eyepiece into the focuser
drawtube and secure it in place with the thumbscrews.

4. Getting Started

Balancing the Telescope

To insure smooth movement of the telescope on both axes of
the equatorial mount, it is imperative that the optical tube be
properly balanced. We will first balance the telescope with
respect to the R.A. axis, then the Dec. axis.

1. Keeping one hand on the telescope optical tube, loosen
the R.A. lock knob. Make sure the Dec. lock knob is
locked, for now. The telescope should now be able to
rotate freely about the R.A. axis. Rotate it until the coun­terweight shaft is parallel to the ground (i.e., horizontal).

2. Now loosen the counterweight lock knob and slide the
weight along the shaft until it exactly counterbalances the
telescope (Figure 3a). That’s the point at which the shaft

remains horizontal even when you let go of the telescope
with both hands (Figure 3b).

3. Retighten the counterweight lock knob. The telescope is
now balanced on the R.A.axis.

4. To balance the telescope on the Dec. axis, first tighten
the R.A. lock knob, with the counterweight shaft still in the
horizontal position.

5. With one hand on the telescope optical tube, loosen the
Dec. lock knob. The telescope should now be able to
rotate freely about the Dec. axis. Loosen the tube ring
clamps a few turns, until you can slide the telescope tube
forward and back inside the rings (this can be aided by
using a slight twisting motion on the optical tube while
you push or pull on it) (Figure 3c).

6. Position the telescope so it remains horizontal when you
carefully let go with both hands.This is the balance point
(Figure 3d). Before clamping the rings tight again, rotate
the telescope so the eyepiece is at a convenient angle for
viewing. When you are actually observing with the tele-

Figure 3a. Proper orientation of the equatorial mount requires

that the telescope tube be balanced on both the R.A. and Dec.
axes.With the R.A.lock knob released, slide the counterweight
along the counterweight shaft until it just counterbalances the tube.

Figure 3b. When you let go with both hands, the tube should not

drift up or down.

Figure 3c. With the Dec. lock knob released, loosen the tube

ring lock clamps a few turns and slide the telescope forward or back
in the tube rings.

Figure 3d. When the tube is balanced about the Dec. axis, it will

not move when you let go.