Orion SKYWATCHER 9086, SKYWATCHER 9024, SKYWATCHER 9025 User Manual

IN 112 Rev. A 0399

Providing Exceptional Consumer Optical Products Since 1975

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INSTRUCTION MANUAL

Orion

®

Skywatcher

™

90mm EQ

#9024 Equatorial Refracting Telescope

2

Figure 1. Skywatcher 90 EQ Parts Diagram

Tube ring mounting plate
Dec. lock knob
Dec. setting circle
R.A. lock knob
R.A. slow-motion control
Counterweight locking thumbscrew
Counterweight
Counterweight shaft
Latitude locking t-bolt
Azimuth adjustment knob

Accessory tray bracket
attachment point

Tripod leg lock knob

Piggy back camera adapter

Tube mounting rings

Finder scope bracket

Finder scope

Alignment screws (3)

Eyepiece

Star diagonal

Focus knob

Dec. slow-motion control

R.A. setting circle

Latitude adjustment t-bolt

Accessory tray bracket

Accessory tray

3

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
1 Mirror star diagonal (1.25")
1 25mm (36x) Kellner eyepiece (1.25")
1 10mm (91x) Kellner 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 Section 1 are present. Save the box es
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
20 minutes. No tools are needed other than the ones provid­ed. All bolts should be tightened securely to eliminate flexing
and wobbling, but be careful not to o v er-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 lensesof the

C

ongratulations on your purchase of a quality Orion telescope.

Your new Skywatcher 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. Lear n 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 f or y our telescope.Please read them ov er
thoroughly before getting started.

Table of Contents

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

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

3. Balancing the Telescope.......................................................................................................4

4. Aligning the Finder Scope.................................................................................................... 5

5. Setting Up and Using the Equatorial Mount ......................................................................... 5

6. Using Your T elescope-Astronomical Observing.................................................................... 7

7. Astrophotography................................................................................................................. 9

8. Terrestrial Viewing................................................................................................................. 10

9. Care and Maintenance......................................................................................................... 10

10. Specifications........................................................................................................................ 10

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.

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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 w ar­ranty 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 by sliding the bolts
installed in the tops of the tripod legs into the slots at the
base of the mount and tightening the wingnuts finger-tight.
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 shor test (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
apart enough to connect each end of the accessory tray
bracket to the attachment point on each leg. Use the bolt
that comes installed in each attachment point to do this.
First remove the bolt, then line up one of the ends of the
bracket with the attachment point and reinstall the bolt.
Make sure the smooth side of the accessory tray bracket
faces upwards.

4. Now , with the accessory tra y br acket 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 3 wingnut-head bolts already installed in
the tray. This is done by pushing the bolts up through the
holes in the accessory tray bracket, and then threading
them into the holes in the accessory tray.

5. Next, tighten the bolts 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 hash mark at “40.”) To do this, loosen the
latitude locking t-bolt, and turn the latitude adjustment t­bolt 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 locking thumbscrew is ade­quately loosened so the metal pin the thumbscrew 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 locking thumbscrew still
loose, grip the counterweight with one hand and thread
the shaft into the 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 locking
thumbscrew.

9. Attach the two tube rings to the equatorial head using the
bolts that come installed in the bottom of the rings. First
remove the bolts, then push the bolts, 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 bolts 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
setscrew on the end of the cable over the indented slot on
the worm gear shaft.Then tighten the setscrew.

12. Place the finder scope in the finder scope bracket by first
backing off all three alignment screws until the screw tips
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 in the
middle of the finder scope.Slide the ey epiece end (narrow
end) of the finder scope into the end of the bracket’s cylin­der that does not have the adjustment screws. Push the
finder scope through the bracket until the groove on the
eyepiece end of the finder scope lines up with the three
adjustment screws.The O-r ing should seat just inside the
front opening of the bracket’s cylinder. Tighten the three
alignment screws equally to secure the finder scope in
place. You may need to first back off the knurled locking
nuts on the adjustment screws to do this.

13. Insert the base of the finder scope bracket into the dove­tail slot on the top of the focuser housing.Lock the br ac k et
in position by tightening the knurled setscrew on the dov e­tail 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

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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 locking thumbscrew and
slide the weight along the shaft until it exactly counterbal­ances the telescope. (Figure 2a) That’s the point at which
the shaft remains horizontal even when you let go with
both hands (Figure 2b).

3. Retighten the counterweight locking thumbscrew. 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 (Figure 2c). 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 2d).

6. Position the telescope in the mounting rings so it remains
horizontal when you carefully let go with both hands.This
is the balance point for the optical tube with respect to the
Dec. axis (Figure 2e).

7. Retighten the tube ring clamps.

The telescope is now balanced on both axes.Now when you
loosen the lock knob on one or both axes and manually point
the telescope, it should move without resistance and should
not drift from where you point it.

4. Aligning the Finder Scope

A finder scope has a wide field of view to facilitate the loca­tion of objects for subsequent viewing through the main
telescope, which has a much narrower field of view. The find­er scope and the main telescope must be aligned so they
point to exactly the same spot in the sky.

Alignment is easiest to do in daylight hours. First, inser t the
lowest-power (25mm) eyepiece into the star diagonal. Then
loosen the R.A. and Dec. lock knobs so the telescope can be
moved freely.

Point the main telescope at a discrete object such as the top
of a telephone pole or a street sign that is at least a quarter­mile away. Move the telescope so the target object appears in
the very center of the field of view when you look into the eye­piece. Now tighten the R.A. and Dec. lock knobs. Use the
slow-motion control knobs to re-center the object in the field of
view , if it mo ved off-center when you tightened the lock knobs.

Now look through the finder scope. Is the object centered in
the finder scope’s field of view, (i.e., at the intersection of the
crosshairs)? If not, hopefully it will be visible somewhere in
the field of view, so that only fine adjustment of the finder
scope alignment screws will be needed to center it on the
crosshairs. Otherwise you’ll have to make coarser adjust­ments to the alignment screws to redirect the aim of the finder

scope. Make sure the knurled lock nut on each alignment
screw is loosened before making any adjustments.

Once the target object is centered on the crosshairs of the
finder scope, look again in the main telescope’s e y epiece and
see if it is still centered there as well. If it isn’t, repeat the
entire process, making sure not to move the main telescope
while adjusting the alignment of the finder scope.

When the target object is centered on the crosshairs of the
finder scope and in the telescope’s eyepiece, tighten the
knurled lock nuts on the alignment screws to lock the finder
scope into position.The finder scope is now aligned and ready
to be used for an observing session. The finder scope and
bracket can be remov ed from the do v etail for storage, and then
re-installed without changing the finder scope’s alignment.

Note that the image seen through the finder scope appears
upside down.This is normal for astronomical finder scopes.

5. Setting Up and Using
the Equatorial Mount

When you look at the night sky, you no doubt have noticed
that the stars appear to move slowly from east to west over
time. That apparent motion is caused by the Earth’s rotation
(from west to east). An equatorial mount (Figure 3) is
designed to compensate for that motion, allowing you to eas­ily “track” the movement of astronomical objects, thereby
keeping them from drifting out of the telescope’s field of view
while you’re observing.

This is accomplished by slowly rotating the telescope on its
right ascension (polar) axis, using only the R.A. slow-motion
cable.But first the R.A. axis of the mount must be aligned with
the Earth’s rotational (polar) axis—a process called polar
alignment.

Polar Alignment

For Northern Hemisphere observers, approximate polar
alignment is achieved b y pointing the mount’s R.A. axis at the
North Star, or Polaris. It lies within 1 degree of the north
celestial pole (NCP), which is an extension of the Earth’s rota­tional axis out into space. Stars in the Nor thern Hemisphere
appear to revolve around Polaris.

To find Polaris in the sky, look north and locate the patter n of
the Big Dipper (Figure 4). The two stars at the end of the
“bowl” of the Big Dipper point right to Polaris.

Observers in the Southern Hemisphere aren’t so fortunate to
have a bright star so near the south celestial pole (SCP).The
star Sigma Octantis lies about 1 degree from the SCP, but it
is barely visible with the naked eye (magnitude 5.5).

For general visual observation, an approximate polar align­ment is sufficient:

1. Level the equatorial mount by adjusting the length of the
three tripod legs.

2. Loosen the latitude locking t-bolt.Turn the latitude adjust­ing t-bolt and tilt the mount until the pointer on the latitude