ORION TELESCOPES & BINOCULARS Atlas 10 EQ 9874 Instruction Manual

IN 214 Rev. A 12/02

Providing Exceptional Consumer Optical Products Since 1975

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

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P.O. Box 1815, Santa Cruz, CA 95061

INSTRUCTION MANUAL

Orion

®

Atlas™ 10 EQ

#9874 Equatorial Reflector Telescope

2

Figure 1a. The Atlas 10 EQ.

Tube ring mounting plate
Tube ring mounting plate

lock knobs (2)
Declination setting circle
Declination lock lever

Counterweight shaft lock lever
Counterweight shaft
Counterweights

Counterweight lock knobs
“Toe Saver”

Tripod leg

Leg lock lever

Finder scope

Finder scope bracket

Eyepiece

Focus knob

Tube rings

Right ascension
setting circle

Right ascension lock lever

Mirror cell
Latitude scale
Latitude adjustment L-bolts
Center support shaft

(not shown)
Hand controller

Tripod support tray

Table of Contents

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

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

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

4. Balancing the Telescope . . . . . . . . . . . . 5

5. Using Your Telescope . . . . . . . . . . . . . . . 6

6. Setting Up and Using the

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

7. Collimating . . . . . . . . . . . . . . . . . . . . . . 12

8. Astronomical Observing . . . . . . . . . . . . 14

9. Astrophotography . . . . . . . . . . . . . . . . . 17

10. Care and Maintenance . . . . . . . . . . . . . 18

11. Specifications . . . . . . . . . . . . . . . . . . . . 19

1. Unpacking

The entire telescope will arrive in three boxes, one containing
the tripod, one containing the equatorial mount, and the third
box containing the optical tube. Be careful unpacking the
boxes.We recommend keeping the boxes and original pack­aging. In the event that the telescope needs to be shipped to
another location, or returned to Orion for warranty repair, ha v­ing the proper packaging will ensure that your telescope will
survive the journey intact.

Make sure all the parts in the Parts List are present. Be
sure to check each box carefully, as some parts are small.

If anything appears to be missing or broken, immediately
call Orion Customer Support (800-676-1343) or email
[e-mail] for assistance.

2. Parts List

Box #1

1 Tripod
3 Counterweights
1 Tripod support tray

Box #2

1 Equatorial mount
1 Hand controller
1 Battery pack
1 Nylon hook-and-loop adhesive strip

Box #3

1 Optical tube
2 Tube rings
1 Tube ring mounting plate
1 25mm Sirius Plössl eyepiece
1 10mm Sirius Plössl eyepiece
1 9x50 Finder scope
1 Finder scope bracket with O-ring
1 Collimation cap
1 Camera adapter
1 Dust cover

3. Assembly

1. Stand the tripod legs upright and spread the legs out as
far as they will go .Make certain that the leg lock levers are
tightened. Assembly should take no more than 30 min­utes. Refer to Figure 1 during assembly. Assembling the
telescope requires no tools other than the ones provided.

2. Place the base of the equatorial mount onto the tripod
head. Orient the equator ial mount so that the post on the
tripod head lines up with the azimuth adjustment knobs on

3

Congratulations on your purchase of a quality Orion telescope. Your new Atlas 10 EQ is designed for

high-resolution viewing of astronomical objects.With its precision optics, and its superb Atlas mount,
you’ll be able to locate and enjoy thousands of fascinating celestial denizens, including planets, Moon,
and a variety of galaxies, nebulas and star clusters.The built in dual internal DC stepper motor drives will
easily track these objects as they move through the night sky.

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

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.

the equatorial mount (Figure 2).You may need to loosen
the azimuth adjustment knobs on the equatorial mount in
order to fit the mount onto the tripod head.

3. Thread the central support shaft into the equatorial mount
until tight.This will secure the equatorial mount to the tri­pod head.

4. Remove the knob and washer from the bottom of the cen­ter support shaft. Slide the tripod support tray up the bot­tom of the central support shaft until the three tray arms
are touching the legs of the tripod.The flat side of the sup­port tray should be facing up.Make sure the “V” of each
tray arm is against a tripod leg. Place the knob washer on
the center support shaft against the tray, and follow it by
threading the securing knob all the way up the center sup­port shaft until it is tight against the tray .The tripod support
tray provides additional stability for the tripod, and holds
up to five 1.25" eyepieces and two 2" eyepieces.

5. Loosen the counterweight shaft lock lever and let the
counterweight shaft extend into its downward position.
Retighten the lock leve r.

6. Remove the knurled “toe saver” retaining screw on the
bottom of the counterweight shaft and slide all three coun­terweights onto the shaft. Make sure the counterweight
lock knobs are adequately loosened to allow the counter­weight shaft to pass through the hole. Position the coun­terweights about halfway up the shaft and tighten the lock
knobs.Replace the toe saver at the end of the bar.The toe
saver prev ents the counterweights from f alling on y our foot
if the lock knobs happen to come loose.

7. Loosen and open the tube rings on the optical tube and
remove the optical tube from the tube rings. Attach the
tube rings to the mounting plate with the provided screws.
Loosen the two mounting plate securing knobs. Place the
mounting plate, with the tube rings attached, in the dove­tail slot on top of the equatorial mount.Position the mount­ing plate so that it is centered on the dovetail slot.Re-tight­en the mounting plate securing knobs until the mounting
plate is secure.

8. Open the tube rings and lay the telescope optical tube in
the rings at about the midpoint of the tube’s length.Rotate

the tube so that the focuser is at a convenient height for
viewing.Close the tube rings and tighten them.

9. Inser t the plug on the end of the control cable from the
hand controller into its jack on the side of the equatorial
mount.

10.Inser t eight D-cell batteries into the batter y pack. Orient
the batteries as indicated on the white plastic battery hold­er.Plug the battery cord into its jack on the mount.

11.Two strips of nylon adhesive (one strip of “hooks”and one
strip of “loops”) have been provided so you can create a
place to keep the hand controller out of the way when not in
use. Place the “hooks” strip of nylon adhesive on the back
of the hand controller and the “loops”strip on a tripod leg or
on the mount where it will be in a conveniently reached
spot.Simply hang the hand controller by the nylon adhesive
when it is not in use. Make certain when you attach the
nylon adhesive to the mount that the hand controller’s posi­tion will not interfere with the motion of the mount.

Installing the Finder Scope

To place the finder scope (Figure 3a) in the finder scope
bracket, unthread the two black nylon thumbscrews until the
screw ends are flush with the inside diameter of the bracket.

Figure 3b. Pull back on the tensioner and slide the finder scope

into its bracket until the O-ring is seated in the bracket ring.

Figure 3a. The 9x50 finder scope and bracket.

4

Tensioner

Eyepiece

Nylon
alignment
thumbscrew (2)

Focusing lock ring

Finder
scope

Finder scope
bracket

Figure 2. Orient the equatorial head so that the post on the tripod

lines up with the azimuth adjustment knobs on the equatorial mount.

Azimuth
adjustment
knobs

Post

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 alignment screws while pulling the chrome,
spring-loaded tensioner on the bracket with your fingers
(Figure 3b). Push the finder scope through the bracket until
the O-ring seats just inside the front opening of the bracket
cylinder. Release the tensioner and tighten the two black
nylon thumbscrews a couple of turns each to secure the find­er scope in place. Insert the base of the finder scope bracket
into the dovetail holder on the top of the focuser. Lock the
bracket into position by tightening the kn urled thumbscrew on
the dovetail holder.

Inserting the Eyepiece

Loosen the thumbscrew on the 1.25" adapter (Figure 4) and
remove the small dust cap.Insert the 25mm eyepiece into the
focuser and secure it with the thumbscrew.

Your Atlas 10 EQ is now fully assembled and should resem­ble Figure 1.

Note about the Atlas 10 EQ Mount Weight

The Atlas 10 EQ mount is very heavy. Alone it weighs 54 lbs.
With the optical tube and counterweights it weighs over 120
lbs. Keep this in mind when moving the telescope even small
distances, and use assistance when needed. It is best to
remove the optical tube and counterweights when moving the
mount, or adjusting the length of the tripod legs.

4. Balancing the Telescope

To ensure smooth movement of the telescope on both ax es of
the equatorial mount, it is imperative that the optical tube is
properly balanced. We will first balance the telescope with
respect to the right ascension (R.A.) axis, then the declination
(Dec.) axis.

1. Keeping one hand on the telescope optical tube, loosen
the R.A.lock lever.Make sure the Dec.lock lever is locked,

for now.The telescope should now be able to rotate freely
about the right ascension axis. Rotate it until the counter­weight shaft is parallel to the ground (i.e., horizontal).

2. Now loosen the counterweight lock knobs and slide the
weights along the shaft until they exactly counterbalance
the telescope (Figure 5a). That’s the point at which the
shaft remains horizontal even when you let go with both
hands (Figure 5b).

3. Retighten the counterweight lock knobs. The telescope is
now balanced on the right ascension axis.

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

5. With one hand on the telescope optical tube, loosen the
Dec. lock lever. The telescope should now be able to
rotate freely about the declination axis.

6. Loosen the knurled ring clamps on the tube r ings 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 5c).

7. Position the telescope in the tube 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 5d).

8. Retighten the knurled rings clamps.

The telescope is now balanced on both axes. When you
loosen the lock lever on one or both axes and manually point

Figure 4. The 2" focuser of the Atlas 10 EQ.

5

Focus lock
thumbscrew

Focus
knobs

1.25" eyepiece
adapter

2" eyepiece adapter

Collimation
screw pair
(3)

Figure 5a-d. Proper operation of the equatorial mount requires

that the telescope tube be balanced on the R.A. and Dec. axes. (a)
With the R.A. lock lever released, slide the counterweights down the
counterweight shaft until they just counterbalance the telescope
tube. (b) When you let go with both hands, the tube should not drift
up or down (c) with the Dec. lock lever released, loosen the tube ring
lock clamps a few turns and slide the telescope forward or back in
the tube rings. (d) When the tube is balanced about the Dec. axis, it
will not move when you let go.

a. b.

c. d.

the telescope, it should move without resistance and should
not drift from where you point it.

5. Using Your Telescope

Focusing the Telescope

With the 25mm eyepiece inserted in the focuser, loosen the
R.A. and Dec.lock levers and move the telescope so the front
(open) end is pointing in the general direction of an object at
least 1/4-mile away. Now, with your fingers, slowly rotate one
of the focusing knobs until the object comes into sharp focus.
Go a little bit beyond sharp focus until the image just starts to
blur again, then reverse the rotation of the knob, just to make
sure you’ve hit the exact focus point.

NOTE: The image in the telescope will appear rotated
180° (upside down and reversed left-to-right).This is nor­mal for astronomical scopes.The finder scope view will
also be rotated 180° (see Figure 6).

If you have trouble focusing, rotate the focusing knob so the
drawtube is in as far as it will go .Now look through the eyepiece
while slowly rotating the focusing knob in the opposite direc­tion.You should soon see the point at which focus is reached.

The black nylon thumbscrew on the top of the body of the
focuser (see Figure 4) will lock the focuser drawtube in place
once the telescope is properly focused. Before focusing,
remember to first loosen this thumbscrew.

Viewing with Eyeglasses

If you wear eyeglasses, you may able to keep them on while
you observe, if the eyepiece has enough “eye relief” to allow
you to see the whole field of view.You can try this by looking
through the eyepiece first with your glasses on, and then with
them off, and see if the glasses restrict the view to only a por­tion of the full field. If they do, you can easily observe with
your glasses off by just re-focusing the telescope the needed
amount. If you suffer from severe astigmatism, however, you
may find images noticeably sharper with your glasses on.

Aligning the Finder Scope

The Atlas 10 EQ Deluxe comes with a 9x50 achromatic finder
scope (Figure 3a).The number 9 means six-times magnifica­tion and the 50 indicates a 50mm diameter front lens. The
finder scope makes it easier to locate the object you want to
observe in the telescope, because the finder scope has a
much wider field-of-view.

The Atlas 10 EQ’s finder scope uses a spring-loaded bracket
that makes alignment of the finderscope very easy. As you
turn either of the thumbscrews, the spring in the bracket’ s ten­sioner moves in and out to keep the finder scope secure in
the bracket.

The finder scope must be aligned accurately with the tele­scope for proper use.To align it, first aim the main telescope
in the general direction of an object at least a 1/4 mile away —
the top of a telephone pole, a chimney, etc. Loosen the R.A.
and Dec. lock levers and move the telescope until it is point­ing toward the desired object. Then sight along the tube to
precisely aim the telescope. Turn the focus knob until the
object is properly focused.Retighten the lock levers.

Now look in the finder scope. Is the object visible? Ideally it
will be somewhere in the field of view. If not, some coarse
adjustment to the finder scope bracket’s alignment thumb­screws will be needed until the object comes into the finder
scope’s field of view.

With the image in the finder scope’s field of view, you now
need to fine-adjust the alignment thumbscrews to center the
object on the intersection of the crosshairs. Adjust the aim of
the finder scope by turning the thumbscrews, one at a time,
until the object is centered.

The finder scope alignment needs to be checked before e v ery
observing session. This can easily be done at night, before
viewing through the telescope. Choose any bright star or
planet, center the object in telescope eyepiece, and then
adjust the finder scope bracket’s alignment thumbscrews until
the star or planet is centered on the finder’s crosshairs.

Focusing the finder scope

If, when you look through the finder scope, the images appear
somewhat out of focus, you will need to refocus the finder
scope for your eyes. Loosen the lock ring located behind the
objective lens cell on the body of the finder scope (see Figure
3a).Back the lock ring off by a fe w turns, f or no w. Refocus the
finder scope on a distant object by threading the objective
lens cell in or out of the finderscope body. Precise focusing
will be achieved by focusing the finder scope on a bright star.
Once the image appears sharp, retighten the locking ring
behind the objective lens cell.The finder scope’s focus should
not need to be adjusted again.

Magnification & Eyepieces

Magnification, or power, is determined by the focal length of
the telescope and the focal length of the eyepiece.Therefore,
by using eyepieces of different focal lengths, the resultant
magnification can be varied.

Magnification is calculated as follows:

6

Naked-eye view

View through finder scope and telescope

Figure 6. The view through a standard finder scope and

reflector telescope is rotated 180°.This is tr ue for the Atlas 10 EQ
and its finder scope as well.