ORION TELESCOPES & BINOCULARS AstroView 90mm EQ 9024 Instruction Manual

INSTRUCTION MANUAL

Orion®

AstroView

#9024 Equatorial Refracting Telescope

™

90mm EQ

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

IN 112 Rev. C 05/02

Tube ring mounting plate

Dec. lock knob

Dec. setting circle

R.A. lock knob

R.A. slow-motion control

Counterweight lock knob

Counterweight shaft

Counterweight

Latitude locking T-bolt

Azimuth lock knob

Accessory tray bracket
attachment point

Piggyback camera adapter

Tube mounting rings

Finder scope bracket

Finder scope

Alignment screws (2)

Eyepiece

Star diagonal

Focus knob

Dec. slow-motion control

R.A. setting circle

Latitude adjustment T-bolt

Accessory tray bracket

Tripod leg lock knob

2

Accessory tray

Figure 1. AstroView 90 EQ Parts Diagram

Congratulations on your purchase of a quality Orion telescope. Your new AstroView 90mm EQ Refractor is

designed for high-resolution viewing of astronomical objects. With its precision optics and equatorial mount, you’ll be able to
locate and enjoy hundreds of fascinating celestial denizens, including the planets, Moon, and a variety of deep-sky galaxies,
nebulas, and star clusters.

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; a star wheel, or planisphere,
available from Orion or from your local telescope shop, will greatly help. 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.

Table of Contents

1. Parts List. . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3. Balancing the Telescope. . . . . . . . . . . . . . . 5

4. Aligning the Finder Scope . . . . . . . . . . . . . 6

5. Setting Up and Using the

Equatorial Mount . . . . . . . . . . . . . . . . . . . . 6

6. Using Your Telescope—

Astronomical Observing . . . . . . . . . . . . . . 10

7. Astrophotography . . . . . . . . . . . . . . . . . . . 13

8. Terrestrial Viewing . . . . . . . . . . . . . . . . . . 14

9. Care and Maintenance . . . . . . . . . . . . . . . 14

10. Specifications . . . . . . . . . . . . . . . . . . . . . . 14

1. Parts List

Qty. Description

1 Optical tube assembly

1 German-type equatorial mount

2 Slow-motion control cables

1 Counterweight

1 Counterweight shaft

3 Tripod legs

1 Accessory tray with mounting hardware

1 Accessory tray bracket

2 Optical tube mounting rings (located on optical tube)

1 6x30 achromatic crosshair finder scope

1 Finder scope bracket with O-ring

1 Mirror star diagonal (1.25")

1 25mm (36x) Sirius Plössl eyepiece (1.25")

1 10mm (91x) Sirius Plössl eyepiece (1.25")

1 Objective lens dust cap

4 Assembly Tools (2 wrenches, Phillips-head
screwdriver, flat-head screwdriver key)

2. Assembly

Carefully open all of the boxes in the shipping container.
Make sure all the parts listed in the parts list are present.
Save the boxes and packaging material. In the unlikely event
that you need to return the telescope, you must use the origi­nal packaging.

Assembling the telescope for the first time should take about
30 minutes. No tools are needed other than the ones 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 Figure 1 during the assembly
process.

During assembly (and anytime, for that matter), Do not touch
the surfaces of the telescope objective lens or the lenses of
the finder scope 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 void.

1. Lay the equatorial mount on its side. Attach the tripod
legs one at a time to the mount using the screws installed
in the tops of the tripod legs. Remove the screw from the
leg, line up the holes in the top of the leg with the holes
in the base of the mount, and reinstall the screw so it
passes through the leg and the mount. Make sure that a
washer is between the screw head and the tripod leg and
between the wingnut and tripod leg. Tighten the wingnuts
only finger-tight, for now. Note that the accessory tray
bracket attachment point on each leg should face inward.

2. Tighten the leg lock knobs at the base 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 scope is completely assembled.

3. With the tripod legs now attached to the equatorial mount,
stand the tripod upright (be careful!) and spread the legs

WARNING: Never look directly at the Sun

through your telescope or its finder scope—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.

3

Focus
lock-ring

Alignment thumbscrews

Tensioner

Figure 2a.

The 6x30 finder scope and bracket

apart enough to connect each end of the accessory tray
bracket to the attachment point on each leg. Use the
screw that comes installed in each attachment point to do
this. First remove the screw, then line up one of the ends
of the bracket with the attachment point and reinstall the
screw. Make sure the accessory tray bracket is oriented
so that the ribs in its plastic molding face downward.

4. Now, with the accessory tray bracket attached, spread
the tripod legs apart as far as they will go, until the brack­et is taut. Attach the accessory tray to the accessory
tray bracket with the three wingnut-head screws already
installed in the tray. This is done by pushing the screws
up through the holes in the accessory tray bracket, and
then threading them into the holes in the accessory tray.

5. Next, tighten the screws at the tops of the tripod legs, so
the legs are securely fastened to the equatorial mount.
Use the larger wrench and your fingers to do this.

6. Orient the equatorial mount as it appears in Figure 1,
at a latitude of about 40, (i.e., so the pointer next to the
latitude scale—located directly above the latitude locking
T-bolt—is pointing to the mark at “40.”) To do this, loosen
the latitude locking T-bolt, and turn the latitude adjustment
T-bolt until the pointer and the “40” line up. Then tighten
the latitude locking T-bolt. The declination (Dec.) and right
ascension (R.A.) axes may need repositioning (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.

7. Slide the counterweight onto the counterweight shaft.
Make sure the counterweight lock knob is adequately
loosened so the metal pin the knob pushes against
(inside the counterweight) is recessed enough to allow
the counterweight shaft to pass through the hole in the
counterweight.

8. Now, with the counterweight lock knob still loose, grip the
counterweight with one hand and thread the shaft into the

Figure 2b. Inserting the finder scope into the finder scope bracket

equatorial mount (at the base of the declination axis) with
the other hand. When it is threaded as far in as it will go,
position the counterweight about halfway up the shaft and
tighten the counterweight lock knob.

9. Attach the two tube rings to the equatorial head using the
screws that come installed in the bottom of the rings. First
remove the screws. then push the screws, with the wash­ers still attached, up through the holes in the tube ring
mounting plate (on the top of the equatorial mount) and
re-thread them into the bottom of the tube rings. Tighten
the screws securely with the smaller wrench. Open the
tube rings by first loosening the knurled ring clamps.

10. Lay the telescope optical tube in the tube rings at about
the midpoint of the tube’s length. Rotate the tube in the
rings so the focus knobs are on the underside of the
telescope. Close the rings over the tube and tighten the
knurled ring clamps finger-tight to secure the telescope in
position.

11. Now attach the two slow-motion cables to the R.A. and
Dec. worm gear shafts of the equatorial mount by posi­tioning the thmb screw on the end of the cable over the
indented slot on the worm gear shaft. Then tighten the
thumb screw.

12. To place the finder scope in the finder scope bracket, first
unthread the two black nylon screws 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 (nar­row 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

4

Figure 3a. Balancing the telescope with respect to the R.A.axis

by sliding the counterweight along its shaft.

Figure 3b. The telescope is now balanced on the R.A. axis.

That-is, when hands are released, the counterweight shaft remains
horizontal

Figure 3c. Preparing the telescope to be balanced on the Dec.

axis by first releasing the Dec. lock knob.

tighten the two black nylon screws a couple of turns each
to secure the finder scope in place.

13. Insert the base of the finder scope bracket into the
dovetail slot on the top of the focuser housing. Lock the
bracket in position by tightening the knurled thumbscrew
on the dovetail slot.

14. Insert the chrome barrel of the star diagonal into the
focuser drawtube and secure with the thumbscrew on the
drawtube.

15. Then insert an eyepiece into the star 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.)

3. 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

Figure 3d. Balancing the telescope with respect to the Dec. axis.

As shown here, the telescope is out of blance (tilting).

Figure 3e. Telescope is now balanced on the Dec. axis, i.e., it

remains horizontal when hands are released.

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 with both hands
(Figure 3b).

5