ORION TELESCOPES & BINOCULARS EQ-2 Equatorial Mount 9019 Instruction Manual

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IN 115 Rev.A 0499
Providing Exceptional Consumer Optical Products Since 1975
Customer Support (800) 676-1343 E-mail: support@telescope.com
Corporate Offices (831) 763-7000 P.O. Box 1815, Santa Cruz, CA 95061
INSTRUCTION MANUAL
Orion
EQ-2 Equatorial Mount
#9019
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Figure 1. EQ-2 Equator ial Mount par ts diagram
Dec. slow-motion control
R.A. slow-motion control Latitude adjustment t-bolt
Latitude lock t-bolt
Accessory tray bracket Accessory tray
Dec. lock knob
R.A. lock knob (hidden)
Counterweight lock
thumbscrew
Counterweight
Counterweight shaft
Azimuth lock knob
Leg lock thumbscrew
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1. Parts List
Qty. Description 1 German-type equatorial mount 2 Slow-motion control cables 1 Counterweight 1 Counterweight shaft 3 Tripod legs w/attachment bolts 1 Accessory tray w/mounting hardware 2 Assembly tools (wrench, Phillips-head screwdriver)
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 original boxes and packaging materi­al. In the unlikely event that you need to return the telescope, you must use the original packaging.
Assembling the mount 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
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 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 brack et on each leg should face inward.
2. Tighten the leg lock thumbscrews at the base of the tripod legs. For now, keep the legs at their shortest (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 the acces­sory tray to the bracket on each leg. Use the small screws and wingnuts to do this.
4. Now, with the accessory tray bracket attached, spread the tripod legs apart as far as they will go, until the bracket is taut.Tighten the bolts at the tops of the tripod legs, so the legs are securely fastened to the equatorial mount. Use the wrench and your fingers to do this.
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ongratulations on your purchase of a quality Orion product.
Your new Orion EQ-2 Equatorial Mount was designed to work with many different telescope optical tubes. Designed for astro­nomical use, this precision mount allows convenient manual “tracking” of celestial objects as they mov e slo wly across the sky, so they remain within your eyepiece’s field of view.The setting circles will assist you in locating hundreds of fascinating celestial denizens, including galaxies, nebulas, and star clusters, from their catalogued coordinates. With a little practice and a little patience, you will find that your EQ-2 Equatorial Mount is an in valuable tool f or 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........................................................................................................ 4
5. Setting Up and Using the Equatorial Mount.......................................................................... 5
6. Specifications......................................................................................................................... 7
7. Suggested Accessories.........................................................................................................7
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5. Orient the equator ial 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 lock t-bolt) is pointing to the hash mark at “40.” To do this, loosen the latitude lock t-bolt, and turn the latitude adjustment t-bolt until the pointer and the “40” line up. Then tighten the latitude lock t-bolt. The declination (Dec.) and right ascension (R.A.) axes many 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.
6. Slide the counterweight onto the counterweight shaft.Make sure the counterweight lock 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.
7. With the counterweight lock 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 lock thumbscrew.
8. 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 and then tightening the setscrew.
3. Attaching a Telescope
The EQ-2 Equatorial Mount is designed to hold small to mid-size telescopes weighing up to about 10 lbs. For heavier telescopes, the mount may not provide suffi­cient stability for steady imaging.Any type of telescope can be mounted on the EQ-2, including refractors, Newtonian reflectors, and catadioptrics, provided a proper adapter or pair of tube rings is available to pro­vide secure coupling.
Orion carries a variety of differently sized tube rings and a 1/4"-20 mounting adapter designed exclusively for the EQ-2 mount.One of these items will probably fit 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.
4. Balancing the Telescope
Once the telescope is attached to the equatorial mount, the next step is to balance the telescope. Proper bal­ance 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 adjusted back and forth as it can when tube rings are used.
Assuming you will be using tube rings, 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 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 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 of the telescope with both hands (Figure 2b). If you position the counterweight all the way at the end of the shaft (near the retaining bolt and washer) and it still does not counterbalance the telescope, you will need to purchase an additional counterweight (Orion part number #65024). Retighten the counterweight lock thumbscrew. The telescope is now balanced on the R.A. axis.
3. T o balance the telescope on the Dec.axis, first tight­en the R.A. lock knob, with the counterweight shaft still in the horizontal position.
4. 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 (Figure 2d); this can be aided by using a slight twisting motion on the optical tube while you push or pull on it. Position the telescope so that it remains horizontal when you carefully let go with both hands (Figure 2e).This is the balance point for the Dec. axis. Before clamping the rings tight again, rotate the telescope so the eyepiece is positioned at a convenient angle for viewing (this is not possible if using a 1/4"-20 mounting adapter).
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The telescope is now balanced on both axes.Now when you loosen the lock knob on one or both ax es 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 3) is designed to compensate for that motion, enabling 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 by pointing the mount’s R.A. axis at the Nor th 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 Northern Hemisphere appear to revolve around Polaris.
To find Polaris in the sky, look north and locate the pat­tern of the Big Dipper (Figure 4).The two stars at the end of the “bowl”of the Big Dipper point right to Polaris, which lies at a distance of about five times the separation of the two bowl stars.
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 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, con­sult 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 dis­tance away.
3. Loosen the Dec. lock knob 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 knob.
4. Loosen the azimuth lock 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 lock knob.
The equatorial mount is now approximately polar­aligned for casual observing. More precise polar alignment is required for astrophotography. Several methods exist and are described in many amateur astronomy reference books.
Note: From this point on in your observing session, you should not make any further adjustments in 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.
Tracking Celestial Objects
When you observe a celestial object through the tele­scope, you’ll see it drift slowly across the field of view. To keep it in the field, if your equatorial mount is polar­aligned, just turn the R.A.slow-motion control.The Dec. slow-motion control is not needed for tracking. Objects will appear to move faster at higher magnifications, because the field of view is narrower.
Optional Motor Drives for Automatic Tracking and Astrophotography
An optional DC motor drive (EQ-2M, Orion part #7827) can be mounted on the R.A. axis of the EQ-2 equatori­al mount to provide hands-free tracking. Objects will then remain stationary in the field of view without any manual adjustment of the R.A.slow-motion control.The motor drive is necessary for astrophotography.
Understanding the Setting Circles
The setting circles on an equatorial mount enable the location of astronomical 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
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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 nega­tive sign denotes south of the celestial equator). There are 60 minutes in 1 hour of R.A, and 60 arc-minutes in 1 degree of declination.
The telescope’s R.A.setting circle is scaled in hours, from 1 through 24, with small hash marks in between repre­senting 10-minute increments.The lower set of numbers (closest to the plastic R.A.gear cover) apply to viewing in the Northern Hemisphere, while the numbers above them apply to viewing in the Southern Hemisphere. The Dec. setting circle is scaled in 1° increments.
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 knobs on the equatorial mount, so the telescope optical tube can move freely.
3 Point the telescope at the bright star near the celestial
equator whose coordinates you know. Center the star in the telescope’s field of vie w. Lock the R.A. and Dec. lock knobs.
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 or observing guide the coordinates of an object you wish to view.
1. Loosen the Dec. lock knob and rotate the telescope until the Dec. value from the star atlas matches the reading on the Dec.setting circle.Retighten the lock knob. Note: If the telescope 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 knob and rotate the telescope until the R.A. value from the star atlas matches the reading on the R.A. setting circle. Retighten the lock knob.
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 recalibrated 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.
Confused About Pointing the Telescope?
Beginners occasionally experience some confusion about how to point the mount overhead or in other direc­tions. In Figure 1 the mount 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 undo the mount’s polar alignment. Remember, once the mount is polar­aligned, the telescope should be moved only on the R.A. and Dec. axes.To point the scope overhead, first loosen the R.A. lock knob and rotate the telescope on the R.A. axis until the counterweight shaft is horizontal (parallel to the ground).Then loosen the Dec. lock knob and rotate the telescope until it is pointing straight over­head. The counterweight shaft is still horizontal. Then retighten both lock knobs.
Similarly, to point the telescope directly south, the counterweight 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).
To point the telescope to the east (Figure 5c) or west (Figure 5d), or in other directions, you rotate the tele­scope on its R.A. and Dec. axes. Depending on the altitude of the object you want to observe, the counter­weight shaft will be oriented somewhere between vertical and horizontal.
The key things to remember when pointing the telescope 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!
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6. Specifications
Mount: Ger man-type equatorial Tripod: wood, black Height: 36" to 57" Weight: 19 lbs. Counterweight: 4.8 lb., supplied Maximum Loading Weight: about 10 lbs. Slow-Motion Adjustment: on both R.A. and Dec. axes Setting Circles:R.A.scaled in 10-min. increments, Dec.
scaled in 1° increments, for N or S Hemisphere Altitude Adjustment: 5° to 75°
7. Suggested Accessories
1/4"-20 Adapter (Orion part #10101)
This accessory bolts to the top of the equatorial head and provides a threaded post on which to mount a cam­era 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-2 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 each set.
I.D. 3.0": Orion par t #7369 I.D. 3.5": Orion par t #7370 I.D. 3.9": Orion par t #7371 I.D. 4.6": Orion par t #7372 I.D. 5.5": Orion par t #7373
EQ-2M Motor Drive (Orion part #7827)
This is a small electric motor that attaches to the equa­torial mount. It turns the gear on the R.A. axis at the same rate the Earth rotates on its axis, thereby follow­ing, or “tracking,” the apparent motion of the stars. Automatic tracking k eeps objects from drifting out of the field of view while you’re observing, and is required for astrophotography. Runs on four D-cell batteries.
Extra Counterweight (Orion part #65024)
Required if your telescope does not balance on the R.A. axis with the supplied 4.8-lb. counterweight. The additional counterweight weighs 4.8 lbs.
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Figure 2c. Preparing the telescope to be balanced on
the Dec. axis by first releasing the Dec. lock knob.
Figure 2d. Balancing the telescope with respect to the Dec.
axis. As shown here, the telescope is out of balance (tilting).
Figure 2e.Telescope is now balanced on the Dec. axis,
i.e., it remains horizontal when hands are released.
Figure 2a. Balancing the telescope with respect to the
R.A. axis by sliding the counterweight along its shaft.
Figure 2b.T elescope is no w balanced on the R.A.axis.That is,
when hands are released, counterweight shaft remains horizontal.
Figure 2. Balancing the telescope
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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
RIGHT ASCENSION AXIS
Declination (Dec.) slow-motion control
Latitude adjustment t-bolt Azimuth adjustment knob
Declination (Dec.)
setting circle
Right ascension
(R.A.) setting circle
Right ascension
(R.A.) slow-motion
control
Latitude locking
t-bolt
Latitude scale
Figure 3.The equator ial mount
DECLINATION AXIS
R.A. lock knob
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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.
Figure 5d.Telescope pointing west.
Figure 5. Pointing the telescope
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One-Year Limited Warranty
This Orion EQ-2 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. Dur ing 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, mis­handled, or modified, nor does it apply to normal wear and tear.This warranty gives you specific legal rights, and you may also ha ve other rights, which vary from state to state.For further war­ranty service information, contact: Customer Service Department, Orion Telescopes & Binoculars, P. O. Box 1815, Santa Cruz, CA 95061; (800) 676-1343.
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Orion Telescopes & Binoculars
Post Office Box 1815, Santa Cruz, CA 95061
Customer Support Help Line (800) 676-1343 • Day or Evening
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