Orion 9968 User Manual

INSTRUCTION MANUAL

Orion®

SkyView™ Pro 150mm EQ

#9968 Equatorial Maksutov-Cassegrain Telescope

Providing Exceptional Consumer Optical Products Since 1975

Customer Support (800)-676-1343
E-mail: [e-mail]

Corporate Offices (831)‑763‑7000

89 Hangar Way, Watsonville, CA 95076

IN 258 Rev. B 01/09

Optical tube

Finder scope

Declination lock lever
(opposite‑side)

Right ascension lock lever
(opposite‑side)

Declination slow‑motion
control knob

Safety thumbscrew

Mounting plate securing knob

Counterweight shaft

Counterweights

Counterweight
lock knobs

Finder scope bracket

Eyepiece

Star diagonal

Focus knob (not shown)

Right ascension slow‑motion

control knob

Right ascension axis

rear‑cover

Latitude scale

Latitude adjustment L‑bolts

Center support shaft

2

Tripod support tray

Tripod leg

Leg lock‑knobs

Figure 1. The SkyView Pro 150mm EQ.

Congratulations on your purchase of an Orion telescope. Your new SkyView Pro 150mm EQ is designed

for high‑resolution viewing, and astrophotography of astronomical objects. With its precision optics and
sturdy equatorial mount, you’ll be able to enjoy hundreds of fascinating celestial denizens.

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. Unpacking........................ 3

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

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

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

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

6. Setting Up and Using the

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

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

8. Astrophotography ................. 14

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

10. Specifications .................... 15

11. Appendix: Collimating .............. 16

1. Unpacking

The entire telescope will arrive in one box. Be careful unpack‑
ing the box. We recommend keeping the box and all origi‑
nal packaging. In the event that the telescope needs to be
shipped to another location, or returned to Orion for warranty
repair, having the proper box and packaging will help ensure
that your mount will survive the journey intact.

Make sure all the par ts in the Par ts List are present. Be
sure to check each box carefully, as some parts are small.
If anything appears to be missing or broken, immediate‑
ly call Orion Customer Support (800‑676‑1343) or email
[e-mail] for assistance.

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.

2. Parts List

1 Tripod

1 Equatorial mount

1 Tripod support tray

1 Counterweight shaft

1 Large counterweight

1 Small counterweight

2 Slow‑motion control knobs

1 Right ascension axis rear cover

1 Latitude adjustment L‑bolt

1 Optical tube assembly

1 25mm Sirius Plössl eyepiece

1 10mm Sirius Plössl eyepiece

1 Star diagonal

1 Finder scope

1 Finder scope bracket with O‑ring

1 Dust cover

3. Assembly

Assembling the telescope for the first time should take about
30 minutes. No tools are needed other than the ones provid‑
ed. All screws should be tightened securely, 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’s front meniscus lens or the
lenses of the finder scope or eyepieces with your fingers. The
optical surfaces have delicate coatings on them that can eas‑
ily 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.

1. Stand the tripod legs upright and spread the legs out as far
as they will go. Keep the tripod legs at their shortest (fully
retracted) length, for now; you can extend them to a more
desirable length later, after the scope is fully assembled.

3

Azimuth
adjustment
knobs

Post

Figure 2. Orient the equatorial mount so that the post on the

tripod head lines up between the azimuth adjustment knobs on the
equatorial mount.

Finder scope bracket Nylon

alignment
thumbscrews

Finder scope

Tensioner

Focus lock ring

2. Place the base of the equatorial mount into the tripod head.
Orient the equatorial mount so that the post on the tripod
head lines up between the azimuth adjustment knobs on
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 tri‑
pod head.

4. Remove the knob and washer from the bottom of the cen‑
ter support shaft. Slide the tripod support tray up the bot‑
tom of the central support shaft until the three tray arms
are touching the legs of the tripod. The flat side of the
accessory tray should be facing up. Make sure the “V” of
each tray arm is against a tripod leg. Place the washer
back on the center support shaft against the tray, and
thread 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 five

1.25" eyepieces and two 2" eyepieces.

5. Thread the latitude adjustment L‑bolt into the rear of the
equatorial mount as show in Figure 1.

6. Thread the counterweight shaft into the equatorial mount
at the base of the declination axis until tight. Make sure the
casting at the top of the counterweight shaft is threaded
clockwise as far as it will go before attaching the shaft.
Once the shaft is installed, turn the casting counter‑clock‑
wise until the top of the casting is flush with the mount.

7. Remove the knurled “toe saver” retaining screw on the
bottom of the counterweight shaft and slide both counter‑
weights 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

Figure 3a. The 8x40 finder scope.

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.

prevents the counterweights from falling on your foot if the
lock knobs happen to come loose.

8. Attach the slow‑motion control knobs to the right ascen‑
sion and declination worm gear shafts of the equatorial
mount by sliding them onto the shaft. Line up the flat on
the end of the shaft with the corresponding feature on the
interior of the knob. The knobs can be attached to either
end of the shafts; use whichever end is most convenient.

9. Loosen the black mounting plate securing knob as well
as the metal safety thumbscrew on the top of the equato‑
rial mount. Place the optical tube’s mounting plate in the
dovetail slot so that it is positioned midway in the dovetail
slot. Tighten the mounting plate securing knob and safety
thumbscrew to secure the optical tube.

4

Figure 4a-d. Proper operation of the equatorial mount requires that the telescope tube be balanced on both the right ascension and

Declination axes. (a) With the R.A. lock lever released, slide the counterweights along the counterweight shaft until it just counterbalances the
tube. (b) When you let go with both hands, the tube should not drift up or down. (c) With the Dec. lock knob released, loosen the mounting
plate securing knob and safety thumbscrew a few turns and slide the telescope forward or backward. (d) When the tube is balanced about the
Dec. axis, it will not move when you let go.

10. Place the right ascension rear axis cover on the equatorial
mount.

Installing the Finder Scope

To place the finder scope (Figure 3a) in the finder scope brack‑
et, unthread the two black nylon thumbscrews 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 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 knurled thumbscrew on the dovetail holder.

Inserting the Star Diagonal and Eyepiece

Remove the dust cap from the eyepiece adapter and insert the
chrome barrel of the star diagonal into the eyepiece adapter
and secure it with the thumbscrews. Remove the dust cap from
the star diagonal and insert the 25mm Plössl 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.)

Your telescope is now completely assembled and should
appear as shown in Figure 1.

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 4a). That’s the point at which the
shaft remains horizontal even when you let go of the tele‑
scope with both hands (Figure 4b).

3. Retighten the counterweight lock lever.

4. Loosen the metal safety thumbscrew on the top of the
equatorial mount. Then with one hand on the optical tube,
loosen the mounting plate securing knob (Figure 4c).

5. Slide the optical tube into the dovetail slot until the mount‑
ing plate is positioned midway in the dovetail slot. Retighten
the mounting plate securing knob.

6. Loosen the Dec. lock lever and test the balance of the opti‑
cal tube by letting go with both hands. If the optical tube
does not move in either direction (Figure 4d) then the tube
is balanced in declination. If the optical tube does move,
then retighten the Dec. lock lever and repeat from step 4
above, this time sliding the optical tube to a new position
and testing the balance again.

7. When the tube is balanced in declination, retighten the
metal safety thumbscrew.

The telescope is now balanced in both axes. When you loos‑
en the lock lever on one or both axes of motion and manually
point the telescope, it should not drift from where you point it.

5. Using Your Telescope

4. Balancing the Telescope

To ensure smooth movement of the telescope on both axes
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.
The telescope should now be able to rotate freely about

Focusing the Telescope

With the 25mm eyepiece inserted in the star diagonal, 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 the focus knob 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 reversed
from left to right. This is normal for telescopes that utilize

5

View through finder scope

View through the SkyView Pro 150mm EQ

Figure 5.

down and backwards (rotated 180°). Images through the SkyView
Pro 150mm EQ with its diagonal in place will be reversed from left‑
to right.

Images through the finder scope will appear upside‑

a star diagonal. The finder scope view will be rotated 180°
(see Figure 5).

If you have trouble focusing, rotate the focus knob counter‑
clockwise as far as it will go. Look through the eyepiece while
slowly rotating the focus knob clockwise. You should soon see
the point at which focus is reached.

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 por‑
tion of the full field. If they do, you can easily observe with your
glasses off by just re‑focusing the telescope by 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 SkyView Pro 150mm EQ comes with a 8x40 achromatic
finder scope (Figure 3a). The number 8 means eight‑times
magnification and the 40 indicates a 40mm diameter front
lens. The finder scope makes it easier to locate the subject
you want to observe in the telescope, because the finder
scope has a much wider field of view.

The 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 tele‑
scope for proper use. To align it, first aim the main telescope
at an object at least a 1/4 mile away—the top of a telephone
pole, a chimney, etc. First, loosen the R.A. and Dec. lock
levers and move the telescope until it is pointing towards the
desired object. Then sight along the tube to aim the telescope.

Turn the focus knob until the object is properly focused. Make
sure to position the object in the center of the telescope’s eye‑
piece by turning the R.A. and declination slow‑motion control
knobs (the R.A. and Dec. lock levers must be tightened to use
the slow‑motion control knobs).

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 thumb‑
screws 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
every 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 few turns, for now. Refocus
the finder scope on a distant object by threading the objec‑
tive lens cell in or out of the finderscope body. Precise focus‑
ing 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:

Telescope Focal Length

Eyepiece Focal Length

= Magnification

The SkyView Pro 150mm EQ has a focal length of 1800mm,
which when used with the supplied 25mm eyepiece yields:

1800mm

25mm

= 72x

The magnification provided by the 10mm eyepiece is:

1800mm

10mm

= 180x

The maximum attainable magnification for a telescope is
directly related to how much light it can gather. The larger the
aperture, the more magnification is possible. In general a fig‑
ure of 2x per millimeter of aperture is the maximum attain‑

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