Orion EQ-1 Equatorial Mount 9011 User manual

IN 146 Rev. A 0500
Providing Exceptional Consumer Optical Products Since 1975
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INSTRUCTION MANUAL
Orion®
EQ-1 Equatorial Mount
#9011

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Figure 1. EQ-1 Equatorial Mount parts diagram
Mounting platform
Dec. slow-motion control
Latitude adjustment t-bolt
R.A. slow-motion control
Accessory tray
Accessory tray bracket
Latitude lock t-bolt
Dec. lock thumb screw
(not shown)
Azimuth lock knob
Counterweight shaft
Counterweight
Counterweight lock knob
R.A. lock thumb screw
Tripod leg attachment bolt
Leg lock knob

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1. Parts List
Qty. Description
1 German-type equatorial mount
1 Latitude adjustment t-bolt
2 Slow-motion control cables
1 Counterweight
1 Counterweight shaft
3 Tripod legs
3 Tripod leg attachment bolts with wing nuts
and washers
3 Leg lock knobs
1 Accessory tray
3 Accessory tray screws with wing nuts and washers
1 Assembly tool
2. Assembly
Carefully open all of the boxes in the shipping contain-
er. Make sure all the parts listed in Section 1 are
present. Save the original boxes and packaging materi-
al. In the unlikely event that you need to return the
telescope, you must use the original packaging.Note:
The EQ-1 Equatorial Mount is packaged with one empty interi-
or box; the box is included for structural integrity only.
Assembling the mount for the first time should take
about 30 minutes. No tools are needed, other than the
one provided. All bolts 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.
1. Lay the equatorial mount on its side. Attach the tri-
pod legs, one at a time, to the base of the mount by
sliding a tripod leg attachment bolt through the top of
a leg and through the holes in the base of the mount.
The washers should be on the outside of the tripod
legs. Secure the wing nuts finger-tight. Note that the
hinged accessory tray bracket on each leg should
face inward.
2. Attach and tighten the leg lock knobs at the base of
the tripod legs. For now, keep the legs at their short-
est (fully retracted) length; you can extend them to a
more desirable length later, after the mount is com-
pletely 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 attach the acces-
sory tray to the three hinged tray brackets on the
legs. The slots in the brackets should be positioned
underneath the holes in the three corners of the tray.
Use the three small accessory tray screws and wing
nuts provided to fasten the tray to the brackets. Do
not tighten the wing nuts yet.
Congratulations on your purchase of a quality Orion product. Your new EQ-1 Equatorial Mount
was designed to work with many different telescope optical tubes. With its precision equatorial head,
you’ll be able to easily track astronomical objects over time so that they remain within your eyepiece’s
field of view. The setting circles will help locate hundreds of fascinating celestial denizens, including
galaxies, nebulas, and star clusters. With a little practice and a little patience, you’ll find that your EQ-1
Equatorial Mount is an invaluable tool for getting the most out of your astronomical observing sessions.
These instructions will help you set up and properly use your equatorial mount. Please read them over
thoroughly before getting started.
Table of Contents
1. Parts List................................................................................................................................ 3
2. Assembly ............................................................................................................................... 3
3. Attaching A Telescope ........................................................................................................... 4
4. Balancing the Telescope........................................................................................................ 5
5. Setting Up and Using the Equatorial Mount.......................................................................... 6
6. Specifications....................................................................................................................... 10
7. Suggested Accessories....................................................................................................... 10

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4. With the accessory tray attached loosely, spread the
tripod legs apart as far as they will go, until the
accessory tray brackets are taut. Then tighten the
wing nuts.
5. Next, tighten the wing nuts on the tripod leg attach-
ment bolts at the base of the equatorial mount, so
that the legs are securely fastened. You can use the
provided assembly tool to hold the heads of the
bolts while firmly tightening the wing nuts.
6. Thread the latitude adjustment t-bolt into the hole in
the rear of the equatorial mount (see Figure 2).
Orient the mount as it appears in Figure 2, at a lati-
tude of about 40°, i.e., so that the pointer next to the
latitude scale is pointing to the hash mark at "40." To
do this, loosen the latitude lock t-bolt (central to the
latitude scale), and turn the latitude adjustment t-
bolt until the pointer and the "40" line up. Then
re-tighten the latitude lock t-bolt.You may also need
to rotate the mount about its right ascension (R.A.)
and declination (Dec.) axes (see Figure 2). Do this
by first loosening the R.A. and Dec. lock thumb
screws.
7. Slide the counterweight onto the counterweight
shaft. Make sure the counterweight lock knob is ade-
quately loosened so the counterweight shaft can
pass through the hole in the counterweight.
8. With the counterweight lock knob still loose, grip the
counterweight with one hand and thread the shaft
into the equatorial mount (at the base of the declina-
tion 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. The washer and screw on the end of the
counterweight shaft will prevent the counterweight
from slipping off the shaft and possibly onto your foot
if the counterweight lock knob should come loose
9. Now attach the two slow-motion cables to the R.A.
and Dec. slow-motion shafts (see Figure 2) of the
equatorial mount by positioning the thumb screw on
the end of the cable over the indented slot on the
shaft, then tightening the thumb screw. A cable can
be attached to either end of the R.A. shaft, whichev-
er is most convenient for you. Use the shorter cable
for the R.A. shaft.
3. Attaching a Telescope
The EQ-1 Equatorial Mount is designed to hold small to
mid-size telescopes weighing up to about 7 lbs. For
heavier telescopes, the mount may not provide suffi-
cient stability for steady imaging. Any type of telescope
can be mounted on the EQ-1 Equatorial Mount, includ-
ing refractors, Newtonian reflectors, and cadadioptrics,
provided a proper adapter or set of tube rings is avail-
able to couple the tube to the mount.
Orion carries a variety of differently sized tube rings
and a 1/4"-20 mounting adapter designed exclusively
for the EQ-1 Equatorial Mount. One of these items
probably fits the telescope tube you wish to mount. See
the list of Suggested Accessories at the end of these
instructions, or check the Orion print or online catalogs
for currently available mounting accessories. The
RIGHTASCENSIONAXIS
Latitude adjustment t-bolt
Declination (Dec.)
setting circle
Right ascension (R.A.)
setting circle
Right ascension (R.A.)
slow-motion shaft
Latitude scale
Latitude locking t-bolt
Figure 2. The equatorial mount
DECLINATIONAXIS
R.A. lock knob
Declination (Dec.) slow-
motion shaft

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mounting accessories fasten to the two holes in the top
platform of the equatorial mount.
4. Balancing the Telescope
Once the telescope is attached to the equatorial mount,
the next step is to balance the telescope. Proper bal-
ance is required to insure smooth movement of the
telescope on both axes of the equatorial mount.
If you attach your telescope with a 1/4"-20 adapter, it
may not be possible to balance the scope precisely with
respect to the declination axis, because the telescope
cannot be moved back and forth as it can when tube
rings are used.
Assuming you will be using tube rings, we will first bal-
ance 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 thumb screw. Make sure the
Dec. lock thumb screw is locked, for now. The tele-
scope 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 counterbal-
ances 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).
Retighten the counterweight lock knob. The tele-
scope is now balanced on the R.A. axis.
3. To balance the telescope on the Dec. axis (this is not
possible if using a 1/4"-20 mounting adapter), first
tighten the R.A. lock thumb screw, with the counter-
weight shaft still in the horizontal position.
4. With one hand on the telescope optical tube, loosen
the Dec. lock thumb screw (Figure 3c). The telescope
should now be able to rotate freely about the Dec. axis.
Figure 3a. Balancing the telescope with respect to the
R.A. axis by sliding the counterweight along its shaft.
Figure 3b. Telescope is now balanced on the R.A. axis. That is,
when hands are released, counterweight shaft remains horizontal.
Figure 3c. Preparing the telescope to be balanced on
the Dec. axis by first releasing the Dec. lock knob.

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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
3d). Position the telescope so that it remains horizontal
when you carefully let go with both hands. This is the
balance point for the Dec. axis (Figure 3e). Before
clamping the rings tight again, rotate the telescope so
that the eyepiece is at a convenient angle for viewing.
The telescope is now balanced on both axes. Now when
you loosen the lock thumb screw on one or both axes
and manually point the telescope, it should move without
resistance and should not drift from where you point it.
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 2) is designed to compensate for that
motion, allowing you to easily "track" the movement of
astronomical objects, thereby keeping them from drift-
ing 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;
this is a process called polar alignment.
Polar Alignment
For Northern Hemisphere observers, approximate
polar alignment is achieved by pointing the mount’s
R.A. axis at the North Star, or Polaris. It lies within 1° of
the north celestial pole (NCP), which is an extension of
the Earth’s rotational axis out into space. Stars in the
Northern Hemisphere appear to revolve around Polaris.
To find Polaris in the sky, look north and locate the pat-
tern 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 fortu-
nate to have a bright star so near the south celestial
pole (SCP). The star Sigma Octantis lies about 1° 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 lock t-bolt. Turn the latitude
adjustment t-bolt and tilt the mount until the pointer
on the latitude scale is set at the latitude of your
observing site. If you don’t know your latitude, con-
sult a geographical atlas to find it. For example, if
your latitude is 35° North, set the pointer to +35.
Then retighten the latitude lock t-bolt. The latitude
setting should not have to be adjusted again unless
you move to a different viewing location some dis-
tance away.
3. Loosen the Dec. lock thumb screw and rotate the
telescope optical tube until it is parallel with the R.A.
axis. The pointer on the Dec. setting circle should
read 90°. Retighten the Dec. lock thumb screw.
Figure 3d. Balancing the telescope with respect to the Dec.
axis. As shown here, the telescope is out of balance (tilting).
Figure 3e. Telescope is now balanced on the Dec.
axis, i.e., it remains horizontal when hands
are released.

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4. Loosen the azimuth adjustment knob and rotate the
entire equatorial mount left-to-right so the telescope
tube (and R.A. axis) points roughly at Polaris. If you
cannot see Polaris directly from your observing site,
consult a compass and rotate the equatorial mount
so the telescope points North. Retighten the azimuth
adjustment knob.
The equatorial mount is now approximately polar-
aligned for casual observing. More precise polar
alignment is required for astrophotography. Several
methods exist and are described in many amateur
astronomy reference books and astronomy magazines.
From this point on in your observing session, you should
not make any further adjustments to the azimuth or the
latitude of the mount, nor should you move the tripod.
Doing so will undo the polar alignment. The telescope
should be moved only about its R.A. and Dec. axes.
Use of the R.A. and Dec. Slow-Motion
Control Cables
The R.A. and Dec. slow-motion control cables allow fine
adjustment of the telescope’s position to center objects
within the field of view. Before you can use the cables,
you must manually "slew" the mount to point the tele-
scope in the vicinity of the desired target. Do this by
loosening the R.A. and Dec. lock thumb screws and
moving the telescope about the mount’s R.A. and Dec.
axes. Once the telescope is pointed somewhere close
to the object to be viewed, retighten the mount’s R.A.
and Dec. lock thumb screws.
The object should now be visible somewhere in the
telescope’s (aligned) finder scope. If it isn’t, use the
slow-motion controls to scan the surrounding area of
sky. If the object is still not visible in the finder scope,
you will need to slew the mount again, this time being
more careful to point the telescope closer to what you
wish to view.
When the object is visible in the finder scope, use the
slow-motion controls to center it. Now, look in the tele-
scope with a long focal length (low magnification)
eyepiece. If the finder scope is properly aligned, the object
should be visible somewhere in the field of view. If it is not,
you may need to realign the telescope’s finder scope.
Once the object is visible in the telescope’s eyepiece,
use the slow-motion controls to center it in the field of
view.You can now switch to a higher magnification eye-
piece, if you wish. After switching eyepieces, you can
use the slow-motion control cables to re-center the
image, if necessary.
To find Polaris in the night sky, look north and find the Big Dipper. Extend an imaginary line from the two “Pointer
Stars” in the bowl of the Big Dipper. Go about 5 times the distance between those stars and you’ll reach Polaris,
which lies within 1° of the north celestial pole (NCP).
Figure 4. Finding Polaris
Big Dipper
(in Ursa Major)
Little Dipper
(in Ursa Minor)
N.C.P.
Pointer Stars
Cassiopeia
Polaris

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The Dec. slow-motion control cable can move the tele-
scope a maximum of 25°. This is because the Dec.
slow-motion mechanism has a limited range of mechan-
ical travel. (The R.A. slow-motion mechanism has no
limit to its amount of travel.) If you can no longer rotate
the Dec. control cable in a desired direction, you have
reached the end of travel, and the slow-motion mecha-
nism should be reset. This is done by first rotating the
control cable several turns in the opposite direction from
which it was originally being turned. Then, manually
slew the telescope closer to the object you wish to
observe (remember to first loosen the Dec. lock thumb
screw). You should now be able to use the Dec. slow-
motion control cable again to fine adjust the telescope’s
position.
Tracking Celestial Objects
When you observe a celestial object through the tele-
scope, you’ll see it drift slowly across the field of view.To
keep it in the field, if your equatorial mount is polar-
aligned, just rotate the R.A. slow-motion control. The
Dec. slow-motion control is not needed for tracking.
Objects will appear to move faster at higher magnifica-
tions, because the field of view is narrower.
Optional Motor Drives for Automatic
Tracking and Astrophotography
An optional DC motor drive (EQ-1M, Orion part #7826)
can be mounted on the R.A. axis of the EQ-1 Equatorial
Mount to provide hands-free tracking. Objects will then
remain stationary in the field of view without any manu-
al adjustment of the R.A. slow-motion control.The motor
drive is necessary for astrophotograpy.
Understanding the Setting Circles
The setting circles on an equatorial mount enable you to
locate celestial objects by their "celestial coordinates."
Every astronomical object resides in a specific location
on the "celestial sphere." That location is denoted by two
numbers: its right ascension (R.A.) and declination
(Dec.). In the same way, every location on Earth can be
described by its longitude and latitude. R.A. is similar to
longitude on Earth, and Dec. is similar to latitude. The
R.A. and Dec. values for celestial objects can be found
in any star atlas or star catalog.
So, the coordinates for the Orion Nebula listed in a star
atlas will look like this:
R.A. 5h 35.4m Dec. -5° 27'
That’s 5 hours and 35.4 minutes in right ascension, and
-5 degrees and 27 arc-minutes in declination (the nega-
tive sign denotes south of the celestial equator). There
are 60 minutes in 1 hour of R.A and there are 60 arc-
minutes in 1 degree of declination.
The mount’s R.A. setting circle is scaled in hours, from
1 through 24, with small hash marks in between repre-
senting 10 minute increments. The numbers closest to
the R.A. axis gear apply to viewing in the Southern
Hemisphere, while the numbers above them apply to
viewing in the Northern Hemisphere. The Dec. setting
circle is scaled in degrees, with each small hash mark
representing 2.5°.
Before you can use the setting circles to locate objects,
the mount must be well polar aligned, and the setting
circles must be calibrated. The declination setting circle
was calibrated at the factory, and should read 90° when
the telescope optical tube is parallel with the R.A. axis.
Calibrating the Right Ascension
Setting Circle
1. Identify a bright star near the celestial equator and
look up its coordinates in a star atlas.
2. Loosen the R.A. and Dec. lock thumb screws on the
equatorial mount, so the telescope optical tube can
move freely.
3 Point the telescope at the bright star near the celes-
tial equator whose coordinates you know. Center the
star in the telescope’s field of view. Lock the R.A. and
Dec. lock thumb screws.
4. Rotate the R.A. setting circle so the pointer indicates
the R.A. listed for the bright star in the star atlas.
Finding Objects With the Setting Circles
Now that both setting circles are calibrated, look up in a
star atlas the coordinates of an object you wish to view.
1. Loosen the Dec. lock thumb screw and rotate the tel-
escope until the Dec. value from the star atlas
matches the reading on the Dec. setting circle.
Retighten the lock thumb screw. Note: If the tele-
scope is aimed south and the Dec. setting circle
pointer passes the 0° indicator, the value on the Dec.
setting circle becomes a negative number.
2. Loosen the R.A. lock thumb screw and rotate the tel-
escope until the R.A. value from the star atlas
matches the reading on the R.A. setting circle.
Retighten the lock thumb screw.
Most setting circles are not accurate enough to put an
object dead-center in your finder scope’s field of view,
but they’ll get you close, assuming the equatorial mount
is accurately polar-aligned. The R.A. setting circle
should be re-calibrated every time you wish to locate a
new object. Do so by calibrating the setting circle for the
centered object before moving on to the next one.

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Confused About Pointing the Telescope?
Beginners occasionally experience some confusion
about how to point the telescope overhead or in other
directions. In Figure 1 the telescope is pointed north as
it would be during polar alignment. The counterweight
shaft is oriented downward. But it will not look like that
when the telescope is pointed in other directions. Let’s
say you want to view an object that is directly overhead,
at the zenith. How do you do it?
One thing you DO NOT do is make any adjustment to
the latitude adjustment t-bolt.That will nullify the mount’s
polar alignment. Remember, once the mount is polar-
aligned, the telescope should be moved only on the R.A.
and Dec. axes. To point the scope overhead, first loosen
the R.A. lock thumb screw and rotate the telescope on
the R.A. axis until the counterweight shaft is horizontal
(parallel to the ground). Then loosen the Dec. lock
thumb screw and rotate the telescope until it is pointing
straight overhead. The counterweight shaft is still hori-
zontal. Then retighten both lock thumb screws.
Similarly, to point the telescope directly south, the coun-
terweight shaft should again be horizontal. Then you
simply rotate the scope on the Dec. axis until it points in
the south direction. (Figure 5a)
What if you need to aim the telescope directly north, but
at an object that is nearer to the horizon than Polaris?
You can’t do it with the counterweight down as pictured
in Figure 1. Again, you have to rotate the scope in R.A.
so that the counterweight shaft is positioned horizontally.
Then rotate the scope in Dec. so it points to where you
want it near the horizon. (Figure 5b)
Figure 5d. Telescope pointing west.
Figure 5a.Telescope pointing south. Note that in all these
illustrations, the mount and tripod remain stationary; only the
R.A. and Dec. axes are moved.
Figure 5b. Telescope pointing north.
Figure 5c. Telescope pointing east.

To point the telescope to the east (Figure 5c) or west
(Figure 5d), or in other directions, you rotate the tele-
scope on its R.A. and Dec. axes. Depending on the
altitude of the object you want to observe, the counter-
weight shaft will be oriented somewhere between
vertical and horizontal.
The key things to remember when pointing the tele-
scope is that a) you only move it in R.A. and Dec., not in
azimuth or latitude (altitude), and b) the counterweight
and shaft will not always appear as it does in Figure 1.
In fact it almost never will!
6. Specifications
Mount: German-type equatorial
Tripod: aluminum
Height: 36" to 57"
Weight: 11.9 lbs
Counterweight: 5 lb. supplied
Maximum Loading Weight: about 7 lbs
Slow-Motion Adjustment: both RA and Dec axes
Setting Circles: RA scaled in 10 min. increments, Dec
scaled in 2.5° increments, for N or S Hemisphere
Polar Axis Altitude Adjustment: 10° to 70°
7. Suggested Accessories
1/4"-20 Adapter (Orion part #10103)
This accessory bolts to the top of the equatorial head
and provides a threaded post on which to mount a cam-
era or telescope that utilizes a standard 1/4"-20 thread.
Tube Mounting Rings
These quality metal rings are custom-made for use with
the EQ-1 Mount. They are hinged for easy installation of
a telescope tube and are lined with felt to prevent
scratching. Check the outer diameter of your telescope;
if it matches the inner diameter (I.D.) of the rings, then
the rings will fit. If the outer diameter of your telescope
is a little smaller than the I.D. of the rings, that is also
acceptable; you can "shim" the inside of the rings with
extra felt. Two rings are included in a set.
I.D. 3.0": Orion part #7369
I.D. 3.5": Orion part #7370
I.D. 3.9": Orion part #7371
I.D. 4.6": Orion part #7372
I.D. 5.5": Orion part #7373
EQ-1M Motor Drive (Orion part #7826)
This is a small electric motor that attaches to the equato-
rial mount. It turns the gear on the R.A. axis at the same
rate that the Earth rotates on its axis, thereby following, or
"tracking," the apparent motion of the stars. Automatic
tracking keeps objects from drifting out of the field of view
while you’re observing, and is required for astrophotogra-
phy. Runs on four size "D" alkaline batteries.
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One-Year Limited Warranty
This Orion EQ-1 Equatorial Mount is warranted against defects in materials or workmanship for
a period of one year from the date of purchase. This warranty is for the benefit 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 to: Orion Warranty Repair, 89 Hangar Way, Watsonville, CA 95076. If the
product is not registered, proof of purchase (such as a copy of the original invoice) is required.
This warranty does not apply if, in Orion’s judgment, the instrument has been abused, mis-
handled, or modified, nor does it apply to normal wear and tear. This warranty gives you specific
legal rights, and you may also have other rights, which vary from state to state. For further war-
ranty service information, contact: Customer Service Department, Orion Telescopes &
Binoculars, P. O. Box 1815, Santa Cruz, CA 95061; [phone].
Orion Telescopes & Binoculars
Post Office Box 1815, Santa Cruz, CA 95061
Customer Support Help Line [phone] • Day or Evening