Orion starBlast 4.5 EQ User Manual

INSTRUCTION MANUAL

IN 260 Rev. B 01/09

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

Orion

®

StarBlast

™

4.5 EQ

#9798 Equatorial Newtonian Reflector Telescope

2

Figure 1a.

The StarBlast 4.5 EQ

EZ Finder II reflex sight

Eyepiece

Focuser

Tube rings

Optical tube

Primary mirror cell

Declination slow-motion control

Right ascension slow-motion control

Latitude adjustment T-bolt

Azimuth lock knob

Accessory tray

Declination setting circle

Right ascension setting circle

Counterweight lock knob

Counterweight

Counterweight shaft

Accessory tray

bracket

Leg lock knob

Figure 1b. The StarBlast 4.5’s equatorial mount.

Right ascension

lock knob

Right ascension

setting circle

Latitude scale

Latitude lock T-bolt

Latitude adjustment

T-bolt

Declination lock knob

Declination

setting circle

Azimuth lock knob

Declination (Dec.) axis

Right

Ascension

(R.A.) axis

3

Table of Contents

1. Unpacking 3

2. Parts List 3

3. Assembly 3

4. Getting Started 4

5. Setting Up and Using the

Equatorial Mount 6

6. Collimating the Optics

(Aligning the Mirrors) 9

7. Astronomical Observing 11

8. Care and Maintenance 13

9. Specifications 14

1. Unpacking

The entire telescope system will arrive in one box. Be careful

unpacking the box. We recommend keeping the original ship-

ping containers. In the event that the telescope needs to be

shipped to another location, or returned to Orion for warranty

repair, having the proper shipping containers will help ensure

your telescope will survive the journey intact.

Make sure all the parts in the Parts List are present. Be sure

to check boxes carefully, as some parts are small. If any-

thing appears to be missing or broken, immediately call Orion

Customer Support (800-676-1343) for assistance.

2. Parts List

Qty. Description

1 Optical tube assembly

2 Tube mounting rings

1 Equatorial mount

1 Latitude adjustment T-bolt

2 Slow-motion control cables

3 Tripod legs connected to accessor y

tray bracket

1 Tripod accessory tray

1 Counterweight shaft

1 Counterweight

1 EZ Finder II reflex sight with mounting

bracket

1 15mm Expanse eyepiece

1 6mm Expanse eyepiece

1 Collimating cap

3. Assembly

Assembling the telescope for the first time should take

about 30 minutes. All screws should be tightened secure-

ly to eliminate flexing and wobbling, but be careful not to

over-tighten or the threads may strip. Refer to Figures 1a.

and 1b. during assembly.

During assembly (and anytime, for that matter), Do not touch the

surfaces of the telescope mirrors or the lenses of the EZ Finder

II or eyepieces with your fingers; the optical surfaces have coat-

ings on them that can be damaged. Never remove any lens

assembly from its housing for any reason, or the product war-

ranty and return policy will be void.

1. Lay the equatorial mount on its side. Attach the tripod legs

one at a time to the mount using the screws installed in

the tops of the tripod legs. Remove the screws, washers,

and wingnuts from the tripod legs, then line up the holes

in the tops of the tripod legs with the holes in the base

of the mount. Reinstall the screws so they pass through

the legs and the mount. Place one washer on each screw

before doing this. After the screws are though the legs and

mount, place a washer and wingnut on each screw end

(Figure 2). Tighten the wingnuts only finger-tight, for now.

2. Tighten the leg lock knobs on the bottom braces of the

tripod legs. For now, keep the legs at their shortest (fully

retracted) length; you can extend them to a more desir-

able length later, after the tripod is completely assembled.

3

Congratulations on your purchase of an Orion telescope.Your new StarBlast 4.5 EQ is a terrific starter

instrument for exploring the exotic wonders of the night sky. Designed to be compact and easy to use, it

will provide many hours of enjoyment for the whole family.

If you have never owned a telescope before, we would like to welcome you to amateur astronomy. Take

some time to familiarize yourself with the night sky. Learn to recognize the patterns of stars in the major

constellations. With a little practice, a little patience, and a reasonably dark sky away from city lights,

you’ll find your telescope to be a never-ending source of wonder, exploration, and relaxation.

These instructions will help you set up, properly use, and care for your telescope. Please read them over

thoroughly before getting started.

WARNING: Never look directly at the Sun through

your telescope—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.

4 4

3. Stand the tripod and mount upright and spread the tripod

legs apart as far as they will go, until the accessory tray

bracket is taut. Connect the accessory tray to the acces-

sory tray bracket with the three wing screws already

installed in the tray. Do this by pushing the wing screws

up through the holes in the accessory tray bracket and

threading them into the holes in the accessory tray.

4. Next, tighten the screws at the tops of the tripod legs,

so the legs are securely fastened to the mount. Use the

Phillips head screwdriver and your fingers to do this.

5. Install the latitude adjustment T-bolt into the threaded hole

in the rear of the mount (Figure 3).

6. Orient the equatorial mount as it appears in Figure 1b. To

do this, first loosen the latitude lock T-bolt, and turn the lati-

tude adjustment T-bolt until the latitude scale pointer and

the “40” on the latitude scale line up. Then retighten the

latitude lock T-bolt. The declination (Dec.) and right ascen-

sion (R.A.) axes will need re-positioning (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 oriented as shown in Figure 1b.

7. Thread the counterweight shaft into the equatorial mount

at the base of the declination axis until tight.

8. Remove the screw and washer on the bottom of the coun-

terweight 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 screw and

washer on the end of the shaft.

9. Attach the two tube rings to the equatorial mount using

the hex head screws that come installed in the rings.

Remove the screws, then push them, with the washers

still attached, up through the holes in the tube ring mount-

ing plate (on the top of the equatorial mount) and rethread

them into the bottom of the tube rings. Tighten the screws

securely with the included wrench. Open the tube rings by

loosening their knurled ring clamps.

10. Attach the two slow-motion control cables to the R.A. and

Dec. worm gear shafts of the equatorial mount by posi-

tioning the thumbscrew on the end of the cable over the

indented slot on the worm gear shaft and then tightening

the thumbscrew. We recommend the shor ter cable be

used on the R.A. worm gear shaft and the longer cable

on the Dec. worm gear shaft. You can install slow-motion

control cable on either end of the R.A. worm gear shaft;

use whichever end is most convenient.

11. Loosen and remove the reflex sight securing thumbnuts

from the optical tube assembly. Place the holes in the base

of the EZ Finder’s bracket over the two threaded shafts

coming out of the optical tube. Replace the thumbnuts to

secure the reflex sight to the optical tube. Refer to Figure

1a for the proper orientation of the EZ Finder II.

13. Remove the cap from the focuser and insert the 15mm

Expanse eyepiece into the focuser drawtube. Secure it in

place with the thumbscrews on the end of the drawtube.

Your StarBlast 4.5 EQ is now fully assembled and should resem-

ble Figure 1a. Leave the dust cover on the front of the optical

tube when it is not in use.

4. Getting Started

Now that the StarBlast 4.5 is assembled, the next things to do

are to balance the telescope about its axes of motion, and to

align the reflex sight with the telescope.

Balancing the Telescope

To insure smooth movement of the telescope on both axes of the

equatorial mount, it is imperative that the optical tube be properly

balanced. First balance the telescope with respect to the R.A.

axis, then the Dec. axis.

Figure 2. Attach the tripod legs to the mount with the screws that

come installed in the tops of the tripod legs. One washer should go

between the screw head and tripod leg and the other washer should

go between the wingnut and tripod leg.

Figure 3. The latitude adjustment T-bolt goes into the threaded

hole in the rear of the mount.

Washer

Wingnut

Screw end

Screw

head

Washer

Threaded hole

Latitude

adjustment T-bolt

55

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 knob and slide the

weight along the shaft until it exactly counterbalances the

telescope (Figure 4a). That’s the point at which the shaft

remains horizontal even when you let go of the telescope

with both hands (Figure 4b).

3. Retighten the counterweight lock knob. The telescope is

now balanced on the R.A. axis.

4. To balance the telescope on the Dec. axis, first tighten the

R.A. lock knob, with the counterweight shaft still in the hori-

zontal position.

5. With one hand on the telescope optical tube, loosen the

Dec. lock knob. The telescope should now be able to rotate

freely about the Dec. axis. Loosen the knurled tube ring

clamps a few turns, until you can slide the telescope tube

forward and back inside the rings (Figure 4c). Using a slight

twisting motion on the optical tube can help move the tube

within the rings.

6. Position the telescope so it remains horizontal when you

carefully let go with both hands (Figure 4d). This is the

balance point. Before clamping the tube rings tight again,

rotate the telescope so the eyepiece is at a convenient

angle for viewing. When you are actually observing with

the telescope, you can adjust the eyepiece position by

loosening the tube rings and rotating the optical tube.

7. Retighten the tube ring clamps.

The telescope is now balanced on both axes. Now when you

loosen the lock knob on one or both axes and manually point the

telescope, it should move without resistance and should not drift

from where you point it.

Focusing the Telescope

With the 15mm Expanse eyepiece in the focuser, move the tele-

scope 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 starts to

blur again, then reverse the rotation of the knob, just to make

sure you’ve hit the exact focus point.

Figure 4.

Proper usage of the equatorial mount requires the telescope tube to be balanced on both the R.A. and Dec. axes. (a) With the

R.A. lock knob 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 knob 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.

4b.4a.

4c. 4d.