Orion ED EQ User Manual

INSTRUCTION MANUAL

SkyView

Equatorial Apochromatic Refractor Telescope

Orion®

™

Pro 100mm ED EQ

#9977

Providing Exceptional Consumer Optical Products Since 1975

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

Corporate Offices [phone]

89 Hangar Way, Watsonville, CA 95076

IN 248 REV C 01/09

Finder scope Finder scope bracket

Tube rings

Tube ring mounting plate

Eyepiece

1.25"
Adapter

2" Star diagonal Focus knob

Latitude adjustment
L-bolts

Declination slow-motion

control knob

Declination lock lever

Right ascension

lock lever

Right ascension slow-

motion control knob

Counterweight shaft

Counterweight

Counterweight

lock knob

“Toe saver”

Tripod support
tray

Figure 1. The SkyView Pro 100mm ED EQ

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Congratulations on your purchase of a quality Orion telescope. Your new SkyView Pro 100mm ED EQ
is an exceptional instrument for observing and imaging astronomical objects. The ED glass of the objec­tive lens ensures you’ll enjoy star, Moon, and planetary images with far less color distortion than seen
in standard refractors. Other features, such as the smooth Crayford focuser, precision machined lens
cell, and deluxe aluminum focusing knobs also attest to the overall high quality of the telescope. With the
sturdy SkyView Pro equatorial mount, you’ll be able to enjoy steady viewing of thousands of the night
sky’s fascinating celestial targets.

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 ...............6

6. Setting Up and Using the

Equatorial Mount................... 8

7. Astronomical Observing ............ 12

8. Terrestrial Observing .............. 15

9. Astrophotography.................16

10. Care and Maintenance .............17

11. Specifications .................... 17

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

Qty. Description

1 Tripod

1 Equatorial mount

1 Tripod support tray

1 Central support shaft (attached to tripod)

1 Tube ring mounting plate

2 Tube rings with mounting screws

1 Counterweight shaft

1 Counterweight

2 Slow-motion control knobs

1 R.A. axis rear cover

2 Latitude adjustment L-bolts

1 Optical tube assembly

1 25mm Sirius Plössl eyepiece, 1.25" barrel diameter

1 10mm Sirius Plössl eyepiece, 1.25" barrel diameter

1 2" Star diagonal with 1.25" adapter

1 Finder scope

1 Finder scope bracket with O-ring

1 Dust cover (attached to optical tube)

1 Camera adapter (attached to optical tube)

1 Small crescent wrench

1. Unpacking

The SkyView Pro 100mm ED EQ will arrive in one box; be care­ful unpacking the box. We recommend keeping the box and all
original 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 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.

3. Assembly

Assembling the telescope for the first time should take about
30 minutes. No tools are needed other than the provided cres­cent wrench. 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 lenses of the telescope, 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 voided.

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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.

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 with 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.

Azimuth
adjustment
knobs

Post

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

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

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 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-bolts into the equatorial
mount where shown in Figure 1. Thread one L-bolt in
about halfway, then thread the other L-bolt in until tight.

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 shaft is threaded counter-clockwise as far
as it will go before attaching the shaft. Once the shaft is
installed, turn the casting clockwise 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 the counterweight
onto the shaft. Make sure the counterweight lock knob is
adequately loosened to allow the counterweight shaft to

pass through the hole. Position the counterweight about
halfway up the shaft and tighten the lock knob. Replace the
toe saver at the end of the bar. The toe saver prevents the
counterweight from falling on your foot if the lock knob hap­pens to come loose.

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

9. Attach the tube mounting rings to the tube ring mounting
plate using the attachment screws that are on the tube
rings. The screws should go through the holes on the outer
ends of the mounting plate and rethread into the tube rings.
Note that the side of the mounting plate with the central
“groove” will be facing up. Use the small crescent wrench
to secure the tube rings to the mounting plate.

10. Loosen the black mounting plate securing knob as well as
the metal safety screw on the top of the equatorial mount.
Place the tube ring 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 knob
until the mounting plate is secure. Then, tighten the safety
screw. The safety screw will ensure that the mounting
plate (and telescope tube) will not fall off the EQ mount if the
mounting plate securing knob should come loose.

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

Installing the Finder Scope

To place the finder scope (Figure 3a) in the finder scope
bracket, 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 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 screws 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 top of
the focuser. Lock the bracket into position by tightening the
knurled thumb screw on the dovetail holder.

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Finder scope bracket

Finder scope

Focus lock ring

Nylon
alignment
thumbscrews

Tensioner

Focuser drawtube Thumb screws

Camera adapter

Figure 4. Before installing the 2" star diagonal, you must remove

the camera adapter that comes attached to the telescope.

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.

Inserting the Diagonal and Eyepiece

The SkyView Pro 100mm ED EQ comes with a camera adapt­er attached to its focuser drawtube. Loosen the two thumb
screws securing the camera adapter to the focuser drawtube
and remove the camera adapter (see Figure 4). Insert the
chrome barrel of the star diagonal into the focuser and secure
it with the thumb screws on the drawtube. The star diagonal
comes with a 1.25" adapter in it; this part allows for use of

1.25" barrel diameter eyepieces in the 2" diameter diago­nal (see Figure 5). Make sure the 1.25" adapter is secure in
the diagonal by tightening the thumb screw on the diagonal.
Loosen the thumb screw on the 1.25" adapter and insert the
barrel of the 25mm eyepiece into it. Secure the eyepiece with
the thumb screw on the 1.25" adapter.

1.25" Barrel diameter eyepiece

1.25" Adapter

a. b.

Figure 5a. and 5b. (a.)To use 1.25" barrel diameter

eyepieces, the 1.25" adapter must be installed in the 2" star
diagonal. (b.) To use 2" eyepieces, remove the 1.25" adapter.

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

2" Star diagonal

2" Barrel diameter eyepiece
(optional)

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,
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 knob and slide the
weight along the shaft until it exactly counterbalances the
telescope (Figure 6a). That’s the point at which the shaft
remains horizontal even when you let go with both hands
(Figure 6b).

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a b c d

Figure 6a - 6d.

(a) With the R.A. lock lever released, slide the counterweight 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 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.

Proper operation of the equatorial mount requires that the telescope tube be balanced on both the R.A. and Dec. axes.

3. Retighten the counterweight lock knob. 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

Naked-eye view

Dec. lock lever. 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 6c).

View through the SkyView Pro 100mm ED EQ

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 6d).

7. Retighten the tube ring clamps.

The telescope is now balanced on both axes. When you loos-

View through finder scope

en the lock lever 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. Using Your Telescope

This section will get you used to the functions and features of
your new telescope.

Focusing the Telescope

With the 25mm eyepiece inserted in the 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 one of the focus 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 reversed
left-to-right. This is normal for astronomical telescopes
that utilize a star diagonal. The finder scope view will be
rotated 180°. (Figure 7)

If you have trouble focusing, rotate the focus knob so the draw­tube is in as far as it will go. Now look through the eyepiece

Figure 7. Images through the SkyView Pro 100mm ED EQ

with its diagonal in place will be reversed from left-to-right. Images
through the finder scope will appear upside-down and backwards
(rotated 180°).

while slowly rotating the focus knob in the opposite direction.
You should soon see the point at which focus is reached.

Note About the Crayford Focuser

The SkyView Pro 100mm ED EQ comes equipped with a
Crayford focuser. The Crayford design allows for smooth,
precise focusing without any image shift that typical rack-and­pinion designs experience. If you find that the focus knobs are
too tight or too loose, you can make adjustments to the focuser
tension by using the focuser tension thumb screw located on
the bottom of the focuser. Make adjustments to this thumb
screw until the focuser motion feels comfortable, but you must
have at least some tension applied to the focuser drawtube,
or else it will not move when you turn the focus knobs.

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 entire field of view. You can try this by look-

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