Meade TRUSS DOBONIAN 10, LIGHT BRIDGE 8, TRUSS DOBONIAN 12, TRUSS DOBONIAN 8, LIGHT BRIDGE10 Instruction Manual

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Instruction Manual

8”, 10", 12" LightBridge™ Truss Tube Dobsonian Telescopes

MEADE.COM

WARNING!

Never use a Meade®Telescope to look at the Sun! Looking at or near the Sun will

cause instant and irreversible damage to your eye. Eye damage is often painless, so there is no warning to the observer that damage has occurred until it is too late. Do not point the telescope or its finder at or near the Sun. Do not look through the telescope or its finder as it is moving.

Children should always

have adult supervision while observing.

WARNING!

Never leave the primary mirror uncovered during the daytime unless using the telescope to view terrestrial objects.

CONTENTS

elescope Features ...................................................... 8

Assembly ........................................................................ 5

Assemble the Base .................................................. 5

Assemble the tube .................................................... 6

t Eyepiece, Attach red dot finder ...................... 7

Inser Collimating the Optical System

Align the red dot finder..............................................11

The deluxe red dot finder ..........................................11

Using a Dobsonian Telescope ..................................11

Calculate Magnification

Observing ......................................................................12

Some Tips ................................................................15

Care of the Optics ....................................................15

Meade Customer Service ..............................................16

Specifications ................................................................17

Optional Accessories......................................................19

............................................12

................................ 8

® The name "Meade" and the Meade logo are trademarks registered with the U.S. Patent and Trademark Office and in principal countries throughout the world. "LightBridge " is a trademark of Meade Instruments Corporation.

Fig. 1 Telescope features.

Tube Assembly

1. Eyepiece

2. Focuser assembly

3. Front OTA (optical tube assembly)

4. Top truss lock knobs (3)

5. Trusses (3)

6. Bottom truss lock knobs (3)

7. Altitude bearing

8. Rear OTA

Inset A: Focuser assembly.

Base Assembly

9. Side base panels (2)

10. Front base panel

11. Circular base plates (2)

12. Feet (3)

Inset A

13. Focus knobs ocus loc

14.

ment knobs

15. 1.25" & 2"eyepiece holder

16. Draw tube

17. Thumbscrew

Inset B

18. Fan

19. Fan battery

pack (inset)

20. Collimation

adjustment screw (3)

21. Collimation

Loc

k & tension adjust

k screw (3)

Inset B: Base of mirror tube.

ASSEMBLY

ASSEMBLE THE BASE

Note: You will need to supply a phillips screwdriver and a one-

ter inch or adjustable wrench to assemble the telescope.

quar Note: Numbers in parentheses. e.g., (9), refer to Fig.1 and Fig. 1

insets

Countersunk depression on this side of base

STEP 1: The base suppor

ts the telescope and allows you to

move the telescope from side to side.

Line up one of the base side panels (9) with the base front panel (10) as shown here. Thread in the two black attachment bolts to secure the panels together. Tighten the bolts to a firm feel.

Repeat with second side panel.

STEP 2: Turn the base panels on their side.

Line up the circular base(11) with the 7 predrilled holes against the panels.

Thread 6 black bolts into the base, as shown here. Make sure that the side with the countersunk holes on the base face the bottom (see photo)

STEP 3:

Slide the center bearing bushing into the 7th (center) hole of the circular base.

Line up the other circular base (sometimes called the ground base), which contains three teflon pads (finger points to a pad) that help the base to move smoothly...

roller bearing

asher

center bearing bushing

STEP 4: ...and place it over the center bearing bushing.

Place a washer over the center bolt.

Place the bolt and washer into the center cylinder.

On the other side of the base, place another washer and an

ut (inset). Tighten the nut to “finger-tight” only

adjustment bolt

attachment n

STEP 3 & 4 DELUXE MODELS ONLY:

Place the center bearing bushing into the countersunk hole of the

round plate. Slide the three roller bearing plates over the center

washers

bearing bushing: First the roller bearing plate, then the roller bearing itself (the plate that looks alike a wagon wheel), then the second roller bearing plate. Place the top part of the base plate assemb

roller

ing

bear plates

the adjustment knob bolt, place two washers on either side of the roller bearing washer. Slide the adjustment bolt through the top base board and into the center bearing bushing and hand-tighten. A nut is captured on the bottom plate. See drawing and photo at left.

ly over the center bearing bushing.To secure in place: On

STEP 5: Next attach the three feet to the bottom panel. Line up

each foot and thread a small attachment screw into the foot to hold it in place. Tighten to a firm feel.

ASSEMBLE THE TUBE

dust cover

seam

front panel

truss knobs

truss

Note: When attaching the feet, make sure that the center countersink depression is on the opposite side of the base

STEP 6: Move the circular panels. They should move easily

about, without any stiffness. If not, tighten or loosen them using a screwdriver while holding the attachment nut in place (with your fingers or a wrench) on the other end of the bolt.

STEP 7: Turn the base so that it is now resting on the feet.

Place the rear OTA (8) into the base. Make sure that the altitude bearings fit snugly into the openings on the side panels of the base. Make sure that the seam of the tube is pointing at the front panel.

Lift to remove the dust cover from the mirror.

STEP 8: Loosen the three bottom truss knobs (6).

Place each truss (5) into a set of slots.

slots

Tighten the truss knobs after all three trusses are in place.

slots

STEP 9: After all 3 trusses are in place, loosen the knob (4) on

top of each truss.

Place the secondary mirror tube (3) into the slots at the top of

each truss....

STEP 10: ...and tighten the truss knobs.

Make sure that the seam on the tube is also pointing towards the front panel (see step 7).

INSERT EYEPIECE AND ATTACH RED DOT FINDER

STEP 10: The entire assembly should move easily up and

down and from side to side.

STEP 11: Insert the one and one quarter inch eyepiece (1) into

ocuser assembly and tighten the focuser thumbscrew (17).

the f To focus the eyepiece, turn the focuser wheels (13) in or out.

If you have the deluxe 2 inch eyepiece, remove the 1.25"

eyepiece holder

holder thumbscrew

eyepiece holder (15) from the focuser assembly by loosening holder thumbscrew (as shown in photo to the left). Slide the 2

yepiece into the focuser and tighten with the eyepiece

inch e

king screw.

loc

ocuser has both a lock knob and a tension adjustment knob.

The f The first lock prevents the draw tube (16) from moving in and out. The second loc locking a focus position into place.

Experiment with these knobs to discover which adjustments are

comfortable with your viewing style.

k locks the focuser knob, thereby

hex screw

top end of slot

thumbscrew

bracket

groove

STEP 12: A red dot finder projects a red dot in place of

crosshairs, to make it easier to line up more precisely with a target.

First, assemble the red dot finder. Slide the bracket over the groove of the red dot finder scope. Tighten the two hex screws with the supplied hex wrench to secure in place.

Slide the red dot finder bracket into the slot on the top OTA. Slide it in from the top (it will only go into the slot from this end). Tighten

ket securely in place.

the thumbscre

w to hold the red dot br

You will need to align the red dot finder. See page 8.

STEP 13: To move the telescope, remove the tube assembly

from the base assembly. Grasp the tube assembly by the trusses and lift up. It is recommended that you relocate the telescope when it is disassembled into two pieces.

STEP 14: Note that there is a fan on the bottom of the mirror

tube. It is powered by a battery pack using 4 AA user-supplied batteries.

ou begin obser

If y heated b “turb

y the sun or b

ulence” your images stabilize and are steady. The fan probably needs to be used less than an hour.

ving at sunset, and the telescope has been

y being in y

our car

, you may notice

in your images. In this case, you can run the fan until

Note also that there are three lock screws and three collimation scre

These scre

ws are f

or use with the collimation procedure.

See page 14.

COLLIMATION OF THE OPTICAL SYSTEM

Precise collimation, or alignment, of your telescope’s optical system is essential for good perf to shipment. You may want to collimate after the telescope has been shipped or if it has endured rough handling or a b touch up is all that's required.

Meade offers an optional laser collimator to help you to collimate your telescope (see

PTIONAL ACCESSORIES, page 18).

O self with the following collimation procedure so that you may recognize a properly collimated instrument and adjust the collimation yourself, if necessary.

Correct Collimation

The collimation procedure for the Meade LightBridge Dobsonian is slightly different from that of other Newtonian reflecting telescopes, because of the "fast" f/5 to f/6 focal ratio of the primary mirror. In typical Newtonian reflectors with more conventional focal ratios (i.e. longer focal ratios), when the observer looks down the focuser tube (without an eyepiece in the focuser), the images of the diagonal mirror, primary mirror, focuser tube and the observer's eye appear centered relative to each other.

However, with the short focal ratio primary mirror of the LightBridge Dobsonian, correct collimation requires that the diagonal mirror be offset in 2 directions: (1) away from the focuser and (2) towards the primary mirror, in equal amounts. This offset is approximately 1/8" in each direction. Note that these offsets have been performed at the factory prior to shipment of your telescope. It is only necessary for you to confirm that the telescope has not been badly jarred out of collimation, and to perform the final fine-tuning of Step 4, below.

Fig. D shows a correctly collimated LightBridge Dobsonian telescope, as it appears when viewed through the focuser

ormance. All Meade telescopes are accurately collimated at the factory prior

umpy car journey—usually, though, just a small

Nevertheless, take the time now to familiarize your-

with the eyepiece removed.

Note: A small paper ring is

attached to the primary mirror. This ring was attached at the factory for purposes of laser collimation. The ring will not diminish your telescope's imaging capabilities and does not need to be removed.

To check and, if necessary, set the optical collimation, follow these steps:

1. Observe through the focuser and orient your body so that the telescope's primary mirror is to your right, and the open end of the telescope tube is to your left.

The diagonal mirror will appear centered as shown ( off center, then adjust the 3 collimation screws ( ror housing.

2. If the reflection of the primary mirror (3, Fig. D) is not centered on the surface of the diagonal mirror, adjust the 3 collimation adjustment screws on the diagonal mirror housing to center the reflection.

As described above, the 3 collimation screws on the diagonal mirror housing are used for two different adjustments during the collimation procedure.

Important Note: Do not force the 3 screws past their normal travel, and do not rotate any screw or screws more than 2 full turns in a counterclockwise direction (i.e., not more than 2 full turns in their "loosening" direction), or else the diagonal mirror may become loosened from its support. Note that the diagonal mirror collimation adjustments are very sensitive: generally turning a collimation screw 1/2-turn will have a dramatic effect on collimation.

3. If the reflection of the diagonal mirror is not centered within the reflection of the primary mirror, adjust the 3 collimation adjustment screws ( rear of the primary mirror cell.

Proceed by "trial and error" until you develop a feel for which collimation screw to turn

en w

in order to change the image in an

m an actual star test to confir

erf

4. epiece, point the telescope at a moderately bright (second or third magni-

26mm e tude) star, and center the image in the main telescope's field of view.

y giv

m the accuracy of steps 1 through 3. Using the

2, Fig. D). If the diagonal appears

2, Fig. B) on the plastic diagonal mir-

20, Fig. C) located on the

- 9 -



Fig. A: Newtonian Reflecting Telescope. (1) Spider Vanes; (2) Secondary Mirror; (3) Parabolic Primary Mirror; (4) Primary Mirror Hex Screws;

ocuser Drawtube; (6) Focused Image.

(5) F

Face-on view Edge-on view

2) 2!

Fig. B: Secondary Mirror Assembly. (1) Spider Vanes; (2) Tilt Screws; (3) Secondary Mirror Holder.

Fig. C: Underside of rear mirror tube (primary mirror housing): (20) Collimation Adjustment Screw; (21) Collimation Lock Screw

b Focuser drawtube c Diagonal mirror d Reflection of primary

mirror

e Reflection of secondary

mirror (darkened due to

back lighting)

f Primary mirror clips g Reflection of observer's eye

b c d e f g

Fig. D: The view you will see while collimating a Schmidt-Newtonian telescope.

Bring the star's image slowly in and out of focus until you see several disks sur-

5. rounding the star's center. If steps 1 through 3 were done correctly, you will see con-

ic (centered with respect to each other) circles (

centr

Fig. E

An improper Adjust the 3 collimating screws on the primary mirror housing until the circles are concentr

In summar tilt of the secondary mirror so that it is correctly centered in the focuser drawtube, and so that the pr

The 3 collimating knobs on the pr that it reflects the light directly up the center of the drawtube.

Fig. E: Correct (1) and incorrect (2) collimation as viewed during a star test.

ly collimated instrument will reveal oblong or elongated circles (2,Fig.E

ic on either side of the focus.

y, the adjustment screws on the plastic diagonal mirror housing change the

imary mirror appears centered when looking into the focuser.

imary mirror change the tilt of the primary mirror so

Intensity Dial

alignment

scre

Rotate the intensity dial to make the red dot more or less intense.

Hex screws

ALIGN THE RED DOT FINDER

It is recommended that you perform steps 1 and 2 of this procedure during the daytime and step 3 at night.

1. If you have not already done so, place the low-power 26mm) eyepiece in the eyepiece holder ( (

e.g., the top of a telephone pole). Turn the focuser knob (13, Fig. 1) so that the

image is sharply focused. Center the object precisely in the main telescope’s field

of vie Rotate the Intensity slider to the brightness level you feel comfortable with. Then,

2. looking through the red dot finder, turn one or both of the red dot finder’s alignment screws until the finder’s red dot points precisely at the same object as centered in the main telescope. The red dot finder is now aligned to the main telescope.

3. Check this alignment on a celestial object, such as the Moon or a bright star, and make any necessary refinements.

15, Fig. 1) and point the telescope at an easy-to-find land object

DELUXE RED DOT FINDER

The deluxe red dot finder is similar to the standard model, except that it provides you with four different red dot indicator shapes: a dot, a cross, a diamond and a bullseye. Rotate the dial on top of the finder to change the intensity. Push the lever below the finder to change the shape of the dot.

The bracket attaches to the finder and the telescope in the same manner that the standard red dot finder attaches (see step #12, page 7).

To align the deluxe finder, adjust the hex screws on the top and side of the finder with the supplied hex wrench. Follow the procedure described in the

FINDER section, above.

ALIGN THE RED DOT

The deluxe red dot finder.

USING A DOBSONIAN TELESCOPE

1. Never lubricate the Teflon pads on the ground plate. Your Dobsonian has been designed with some inherent friction. You want the telescope to move easily when you position it, but you also want it to stay in the position you place it. Using any kind of oil, silicone spray, wax, or grease will ruin the performance by causing the telescope to move too easily. Just keep these bearing surfaces clean; that’s all the maintenance required.

2. The altitude bearing surfaces ( the factory for optimum performance. Over a period of time, these surfaces may become dry or dirty. Simply clean off the bearing surfaces with a dry cloth or paper towel. Do not use solvents or alcohol-based cleaning solutions as this may damage the bearings or the painted surfaces of the telescope.

3. You will notice that your telescope will move in altitude by raising and lowering the tube, and in azimuth by rotating the base. As you observe objects in the night sky they will appear to drift out of the field of view due to the Earth’s rotation. To keep an object centered in the field of view, just lightly nudge the telescope in the proper direction. This may take a little practice at first, but you’ll soon get the hang of it.

4. Be sure the Mount is placed on a relatively level surface to allow proper operation. Each of the three feet should be in firm contact and not wobble. If you are in an area with particularly rough or soft ground, it may be helpful to place the Mount on a thick piece of plywood.

5. Part of the fun of using a Dobsonian type of telescope is the challenge of hunting for objects in the night sky. Invest in some simple star charts and books that tell you how to locate objects using a technique called “star hopping.” Once you begin learning the star patterns and constellations, you’re well on you way to finding

y amazing sights

man

7, Fig 1) of the telescope are lightly lubricated at

CALCULATE MAGNIFICATION

The magnification, or power of a telescope is determined by two factors: the focal length of the e with one eyepiece. The focal length of the eyepiece, 26mm, is printed on its side.

Telescope focal length is the distance that light travels inside the telescope before reaching a focus.

The focal length of the Dobsonian 8" = 1219mm. The focal length of the Dobsonian 10" = 1270mm The focal length of the Dobsonian 12" = 1524mm

To change magnification, change eyepieces.

To calculate the magnification of a given eyepiece, use this formula:

Example: Using the 26mm eyepiece supplied with the 8" f/6, the power is:

The type of eyepiece, whether Modified Achromatic, Plössl, or Super Plössl, has no effect on magnification, but does have a bearing on such optical characteristics as field of view, flatness of field, and color correction.

Maximum practical magnification is about 50X per inch of aperture. Generally, however, lower powers produce higher image resolution. When unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extremely high powers result in distorted magnification and observational details are diminished by the use of excessive power.

When beginning observations on a particular object, always start with a low power eyepiece. Centered the object in the field of view. Sharply focus the object. Then try using a higher power eyepiece. If the image starts to become fuzzy when you use higher magnification, back down to a lower power. The atmosphere is not sufficiently steady to support high powers. Keep in mind that a bright, clearly resolved, but smaller image will show far more detail than a dimmer, poorly resolved larger image.

yepiece and the focal length of the telescope.Your telescope is supplied

Power =Telescope Focal Length

Power =1219mm

___________________ Eyepiece Focal Length

________ = 47x (approx.)

26mm

OBSERVING

Observe during the daytime: Try out your telescope during the daytime at first. It is easier to lear

k out an easy object to obser

Pic

skyscraper make excellent targets. Point the optical tube so it lines up with your object.

Use the red dot finder: If you have not done so, align the red dot finder with the telescope’s eyepiece as described earlier. Look through the finder until you can see the object. It will be easier to locate an object using the finder rather than locating with the eyepiece. Line up the object with the finder’s red dot.

Look through the e

through the optical tube’ the object in your eyepiece.

Focus: Look through the eyepiece and practice focusing on the object you have chosen. lock prevents the draw tube (16) from moving in and out. The second lock locks the focuser knob, thereby locking a focus position into place. Experiment with these knobs to disco

Observe the Moon: When you feel comfortable with the finder, the eyepieces, the

ks and the adjustment controls

loc The Moon is the best object to observe the first time you go out at night. Pick a night when the Moon is a crescent. No shadows are seen during a full Moon, making it appear flat and uninteresting.

n how it operates and how to observe when it is light.

A distant mountain, a large tree

epiece:

ocuser has both a lock knob and a tension adjustment knob. The first

The f

er which adjustments are comf

Once y

s eyepiece. If you have aligned your finder, you will you see

ou will be ready to tr

, y

e the object lined up in the finder

ou ha

le with your viewing style.

tab

y out the telescope at night.

, a lighthouse or

, look

or different features on the Moon:

Look f

ou can see craters within craters. Some craters have bright lines about them. These

y are called rays and are the result of material thrown out of the crater when it was struck by a colliding object. The dark areas on the Moon are called maria and are composed of lava from the period when the Moon still had volcanic activity. You can also see mountain ranges and fault lines on the Moon.

Use a neutral density filter (sometimes called a “moon filter”) when observing the

Neutral density filters are available from Meade as an optional accessory.

Moon.

The most ob

vious features are craters. In fact

Craters of the Moon are excellent targets to observe.

Spend se makes other objects in the sky difficult to see. These are nights that are excellent for lunar observation.

Observe the Solar System: After observing the Moon, you are ready to step up to the next level of observation, the planets. There are four planets that you can easily observe in your telescope: Venus, Mars, Jupiter and Saturn.

Nine planets (maybe more...3 more planets have been discovered in the "Oort" cloud at print time) travel in a fairly circular pattern around our Sun. Any system of planets orbiting one or more stars is called a solar system. Our Sun, by the way, is a single, dwarf star. It is average as far as stars go and is a middle aged star.

Beyond the planets are clouds of comets, icy planetoids and other debris left over from the birth of our sun (the Oort cloud). Recently astronomers have found large objects in this area and they may increase the number of planets in our solar system.

The four planets closest to the Sun are rocky and are called the inner planets. Mercury, Venus, Earth and Mars comprise the inner planets. Venus and Mars can be easily seen in your telescope.

Venus is seen before dawn or after sunset, because it is close to the Sun. You can observe Venus going through crescent phases. But you cannot see any surface detail on Venus because it has a very thick atmosphere of gas.

When Mars is close to the Earth, you can see some details on Mars, and sometimes even Mars’ polar caps. But quite often, Mars is further away and just appears as a red dot with some dark lines crisscrossing it.

veral nights observing the Moon. Some nights, the Moon is so bright that it

The planet Jupiter. Jupiter's four largest moons can be obser different position every night.

ved in a

Jupiter, Saturn, Uranus, Neptune and Pluto comprise the outer planets. These planets, except for Pluto, are made mostly of gases and are sometimes called gas giants. If they had grown much bigger, they may have become stars. Pluto is made mostly

of ice

Jupiter is quite interesting to observe. You can see bands across the face of Jupiter. The more time you spend observing these bands, the more details you will be able to see.

One of the most fascinating sights of Jupiter are its moons.The four largest moons are called the Galilean moons, after the astronomer Galileo, who observed them for the first time. If you’ve never watched the Galilean moons in your telescope before, you’re missing a real treat! Each night, the moons appear in diff

vian sky. This is sometimes called the Galilean dance.On any given night, you might

Jo be able to see the shadow of a moon on the face of Jupiter, see one moon eclipse another or e positions of the moons each night is an excellent exercise for novice astronomers.

Any small telescope can see the four Galilean moons of Jupiter, plus a few others, but how many moons does Jupiter actually have? No one knows for sure! Nor are we sure how many Saturn has either. At last count, Jupiter had over 60 moons, and held a small lead o very large telescopes.

en see a moon emerge from behind J

er Saturn. Most of these moons are very small and can only be seen with

erent positions around the

upiter’

s giant disk.

wing the

ly the most memorable sight you will see in your telescope is Saturn. Although

Probab

ou may not see many features on the surface of Saturn, its ring structure will steal

y your breath away. You will probably be able to see a black opening in the rings, known as the Cassini division.

Saturn is not the only planet that has rings, but it is the only set of rings that can be seen with a small telescope. Jupiter’s rings cannot be seen from Earth at all—the Voyager spacecraft discovered the ring after it passed Jupiter and looked back at it. It

ns out, only with the sunlight shining through them, can the rings be seen. Uranus

tur and Neptune also ha

Optional color filters help bring out detail and contrast of the planets. Meade offers a line of inexpensive color filters.

What’s Next? Beyond the Solar System: Once you have observed our own system of planets, it’s time to really travel far from home and look at stars and other objects. You can observe thousands of stars with your telescope. At first, you may think stars are just pinpoints of light and aren’t very interesting. But look again. There is much information that is revealed in stars.

The first thing you will notice is that not all stars are the same colors. See if you can find blue, orange, yellow, white and red stars. The color of stars sometimes can tell you about the age of a star and the temperature that they burn at.

Other stars to look for are multiple stars. Very often, you can find double (or binary) stars, stars that are very close together. These stars orbit each other. What do you notice about these stars? Are they different colors? Does one seem brighter than the other?

ve faint rings.

M31, the Andromeda galaxy, is one of the easiest galaxies to locate and observe during the fall and winter evenings.

The pleiades is probab striking star cluster to observe in the Northern Hemisphere.

ly the most

Almost all the stars you can see in the sky are part of our galaxy. A galaxy is a large grouping of stars, containing millions or even billions of stars. Some galaxies form a spiral (like our galaxy, the Milky Way) and other galaxies look more like a large football and are called elliptical galaxies. There are many galaxies that are irregularly shaped and are thought to have been pulled apart because they passed too close to—or even through—a larger galaxy.

You may be able to see the Andromeda galaxy and several others in your telescope. They will appear as small, fuzzy clouds.

You will also be able to see some nebulas with your scope. Nebula means cloud. Most nebulas are clouds of gas. The two easiest to see in the Northern Hemisphere are the Orion nebula during the winter and the Trifid nebula during the summer. These are large clouds of gas in which ne of stars exploding. These explosions are called supernovas.

When you become an advanced observer you can look for other types of objects such as asteroids, planetary nebula and globular clusters. And if you’re lucky, every so often a bright comet appears in the sky, presenting an unforgettable sight.

The more you learn about objects in the sky, the more you will learn to appreciate the sights you see in your telescope. Start a notebook and write down the observations y

Use a compass to make a circle, or trace around the lid of a jar. Draw what you see in y of Jupiter every night or so. Try to make Jupiter and the moons approximately the same size as they look in your eyepiece. You will see that the moons are in a different position every night. As you get better at drawing, try more challenging sights, like a crater system on the moon or even a nebula.

e each night.

ou mak

epiece inside the circle

our e

Note the time and the date.

w stars are being born. Some nebulas are the remains

ercise for drawing is to observe the moons

The best e

ary or check out the internet for more information about astronomy. Learn

our libr

Go y about the basics: Light years, orbits, star colors, how stars and planets are formed, red shift, the big bang, what are the different kinds of nebula, what are comets, asteroids and meteors and what is a b the more fun, and the more rewarding your telescope will become.

lac

k hole

The more y

n about astronomy,

ou lear

Venus, in its thin, crescent phase.

SOME TIPS

By the way, you might have noticed something strange when you looked through your eyepiece. The image is upside down, and it is also reversed. That means reading words can be a problem or viewing objects on the ground can be a problem. But it has no affect on astronomical objects.

Objects move in the eyepiece: If you are observing an astronomical object (the Moon, a planet, star, etc.) you will notice that the object will begin to move slowly through the telescopic field of vie makes an object move through the telescope’s field of view. To keep astronomical objects centered in the field, simply move the telescope on one or both of its axes— vertically and/or horizontally as needed. At higher powers, astronomical objects will seem to move through the field of view of the eyepiece more rapidly.

Place the object to be viewed at the edge of the field and, without touching the telescope, watch it drift through the field to the other side before repositioning the telescope so that the object to be viewed is again placed at the edge of the field, ready to be further observed.

Vibrations: Avoid touching the eyepiece while observing through the telescope. Vibrations resulting from such contact will cause the image to move. Avoid observing sites where vibrations cause image movement (for example, near railroad tracks). Viewing from the upper floors of a building may also cause image movement.

Let your eyes “dark-adapt:” Allow five or ten minutes for your eyes to become “dark adapted” before observing. Use a red-filtered flashlight to protect your night vision when reading star maps, or inspecting the telescope. Do not use use a regular flashlight or turn on other lights when observing with a group of other astronomers. You can make your own red filtered flashlight by taping red cellophane over a flashlight lens.

w. This movement is caused by the rotation of the Earth and

Saturn is the perhaps the most unforgettable sight to see in a telescope

Viewing through windows: Avoid setting up the telescope inside a room and observing

through an opened or closed window pane. Images may appear blurred or distorted due to temperature differences between inside and outside air. Also, it is a good idea to allow your telescope to reach the ambient (surrounding) outside temperature before starting an observing session.

When to observe: Planets and other objects viewed low on the horizon often lack sharpness—the same object, when observed higher in the sky, will appear sharper and have greater contrast. Try reducing power (change your eyepiece) if your image is fuzzy or shimmers. Keep in mind that a bright, clear, but smaller image is more interesting than a larger, dimmer, fuzzy one. Using too high a power eyepiece is one of the most common mistak

Dress

Warm:Even on summer nights, the air can feel cool or cold as the night wears

on. It is important to dress warm or to have a sweater, jacket, gloves, etc., nearby.

Know your observing site: If possible, know the location where you will be observing. Pay attention to holes in the ground and other obstacles. Is it a location where wild animals, such as skunks, snakes, etc., may appear? Are there viewing obstructions such as tall trees, street lights, headlights and so forth? The best locations are dark locations skies

Surf the Web and visit your local library: The internet contains a huge amount of astronomical information, both for children and adults. Check out astronomy books from your library. Look for star charts—these are available on a monthly basis in Astronomy and Sky and Telescope magazines.

, the dar

. But it is still possible to observe even in a city.

er the better

es made b

y new astronomers.

. Deep space objects are easiest to see under dark

CARE OF OPTICS

our Meade telescope is a fine instrument. With reasonable care, it will last a lifetime.

Y Maintenance guidelines include:

void cleaning the telescope’s optics: A little dust on the front surface of the tele-

scope’s correcting lens causes virtually no degradation of image quality and should not be considered reason to clean the lens.

. When absolutely necessary, dust on the mirror should be blown off with an ear

syringe (available at any pharmacy). DO NOT use a commercial photographic lens cleaner

c. Organic materials (e.g., fingerprints) on the front lens may be removed with a

solution of 3 parts distilled water to 1 part isopropyl alcohol. You may also add 1 drop of biodegradable dishwashing soap per pint of solution. Use soft, white facial tissues and make short, gentle strokes. Change tissues often.

Caution: Do not use scented or lotioned tissues or damage could result to the optics.

d. If the telescope is used outdoors on a humid night, water condensation on the

telescope surfaces will probably result. While such condensation does not normally cause any damage to the telescope, it is recommended that the entire telescope be wiped down with a dry cloth before the telescope is packed away. Do not, however, wipe any of the optical surfaces. Rather, simply allow the telescope to sit for some time in the warm indoor air, so that the wet optical surfaces can dry unattended.

e. If your

or more, it is advisable to remove the batteries from the battery pack. Batteries left in the telescope for prolonged periods may leak, causing damage.

g. Do not leave your telescope inside a sealed car on a warm summer day; exces-

sive ambient temperatures can damage the telescope’s internal lubrication

telescope is not to be used for an extended period, perhaps for one month

MEADE CUSTOMER SERVICE

If you have a question concerning your LightBridge Truss Tube Dobsonian, contact the Meade Instruments Customer Service Department at (800) 626-3233. Customer Service hours are 8:00 AM to 5:00 PM, Pacific Time, Monday through Friday. In the unlikely event that your LightBridge Dobsonian requires factory servicing or repairs, write or call the Meade Customer Service Department first, before returning the telescope to the factory, giving full particulars as to the nature of the problem, as well as your name, address, and daytime telephone number. The great majority of servicing issues can be resolved by telephone, avoiding return of the telescope to the factory. If factory service is required, you will be assigned a Return Goods Authorization (RGA) number prior to return.

Attach eyepiece tray to side or back base panels.

SPECIFICATIONS

8" Standard Model

TA Open truss design. Upper cage metal tube

containing spider and secondary mirror holder,

ocuser with attachment points for truss tubes.

f Lower metal tube containing mirror cell, altitude

ings, battery powered fan, with truss tube

bear attachment castings and captive bolts and knobs.

Truss tubes Silver anodized aluminum with attachment hardware

and captive bolts. Machined aluminum altitude

Secondary Mirror Support 4-vane, steel Mirror 8"

Focal length 1219mm (48") Focal ratio f/6 Resolving P Limiting visual magnitude 13.5

ocuser 2" Crayford style machined aluminum with 1.25”

Mount Swivel base with Teflon bearings for azimuth. Eyepiece tray For one 2” and three 1.25” eyepieces mounted on

Eyepiece Meade 26mm Super Plössl Dust Cover To fit over primary mirror inside of lower tube. Finder Standard red dot Computer Software CD-ROM of Autostar Suite Astronomer's Edition soft-

Assembled OTA weight 24 lbs. Assembled Mount weight 20 lbs. Total Assembled telescope wt. 44 lbs.

ower 0.74 arc seconds

bearings.

adapter.

one side of the base.

ware

8" Deluxe Model

Includes all the features of the 8" standard model , plus:

Eyepiece Meade 26mm QX Wide Angle Eyepiece. Base bearings Three roller bearing plates Finder Deluxe Red Dot

10" Standard Model

TA Open truss design. Upper cage metal tube

containing spider and secondary mirror holder, focuser with attachment points for truss tubes. Lower metal tube containing mirror cell, altitude bearings, battery powered fan, with truss tube attachment castings and captive bolts and knobs.

Truss tubes Silver anodized aluminum with attachment hardware

and captive bolts. Machined aluminum altitude

Secondary Mirror Support 4-vane, steel Mirror 10"

Focal length 1270mm (50") Focal ratio f/5 Resolving Power 0.56 arc seconds Limiting visual magnitude 14 Focuser 2" Crayford style machined aluminum with 1.25”

Mount Swivel base with Teflon bearings for azimuth.

bearings.

adapter.

epiece tray For one 2” and three 1.25” eyepieces mounted on

one side of the base. Eyepiece Meade 26mm Super Plössl Dust Cover To fit over primary mirror inside of lower tube. Finder Computer Software CD-ROM of Autostar Suite Astronomer's Edition

Assembled OTA weight 38 lbs. Assemb Total Assembled telescope wt. 65 lbs.

led Mount weight 27 lbs.

Standard red dot

are

softw

10" Deluxe Model

Includes all the features of the 10" standard model, plus:

Eyepiece Meade 26mm QX Wide Angle Eyepiece. Base bearings Three roller bearing plates Finder Deluxe Red Dot

12" Standard Model

OTA Open truss design. Upper cage metal tube

containing spider and secondary mirror holder,

focuser with attachment points for truss tubes.

Lower metal tube containing mirror cell, altitude

bearings, battery powered fan, with truss tube

attachment castings and captive bolts and knobs.

All 12 inch models have a triangular ground plate. Truss tubes Silver anodized aluminum with attachment hardware

and captive bolts. Machined aluminum altitude

Secondary Mirror Support 4-vane, steel Mirror 12"

Focal length 1524mm (60") Focal ratio f/5 Resolving Power 0.45 arc seconds Limiting visual magnitude 14.5 Focuser 2" Crayford style machined aluminum with 1.25”

Mount Swivel base with Teflon bearings for azimuth. Eyepiece tray For one 2” and three 1.25” eyepieces mounted on

Counterweight None

epiece Meade 26mm Super Plössl

Ey Dust Cover To fit over primary mirror inside of lower tube. Finder Standard red dot Computer Software CD-ROM of Autostar Suite Astronomer's Edition

Assembled OTA weight 47 lbs. Assembled Mount weight 33 lbs. Total Assembled telescope wt. 80 lbs.

bearings.

adapter.

one side of the base.

software

12" Deluxe Model

Includes all the features of the 12" standard model, plus:

Eyepiece Meade 26mm QX Wide Angle Eyepiece. Base bearings Three roller bearing plates

e Red Dot

Finder

Delux

Fig. 12: Series 5000 5 Element Plossl Eyepieces.

Fig. 13: Series 5000 Super Wide Angle Eyepieces.

OPTIONAL ACCESSORIES

A wide assor telescope models. The premium quality of these accessories is well-suited to the quality of the instr

for complete details on these and other accessories.

Meade Series 4000™ Eyepieces:

ou the magnification that you want, but also give you the eye relief you need. Other

y qualities to look for with eyepieces are the apparent field size, which is how large an object looks in an eyepiece, and coatings, which increase contrast in an image. Meade’s series series 5000 eyepieces incorporate all the features that you’d want in a set of high quality e low and high power eyepiece on hand such as a 9mm ,12mm, and 40mm, in addition to the supplied 26mm. ready to use 2" diameter eyepieces.

Series 5000™ TeleXtenders: An advanced 4-element design doubles, triples or quadruples magnification while flattening the field of view, and the fully coated lenses deliver the maximum light transmission, the highest contrast and an image free of color fringing. Maintains a comfortable eye relief of longer focal length eyepieces, while increasing magnification.

Series 4000™ 8 - 24mm Zoom Eyepiece: The internal zoom optics of this eyepiece move on smooth, precisely machined surfaces which maintain optical collimation at all zoom settings. A scale graduated in 1mm units indicates the zoom focal length in operation. An excellent addition to any eyepiece set.

Series 4000™ Photo-Visual Color Filters: Color filters significantly enhance visual and photographic image contrast of the Moon and planets. Each filter threads into the barrel of any Meade 1.25" eyepiece, and into the barrels of virtually all other eyepiece brands as well. Meade filters are available in 12 colors for lunar and planetary applications, and in Neutral Density as a lunar glare-reduction filter.

Series 4000™ Nebular Filters: A modern boon to the city-dwelling deep-space observer, the interference nebular filter effectively cancels out the effects of most urban light pollution, while leaving the light of deep-space nebular emissions virtually unattenuated. Meade coating technology.

tment of professional Meade accessories is available for the LightBridge

ument itself.

yepieces. It is recommended that observers have two or three

And remove the 1.25 eyepiece holder and your LightBridge is

Consult the Meade General Catalog or meade

You want to select an eyepiece that not only gives

Series 4000 Nebular Filters utilize the very latest in

.com

14:

15:

ies 5000 Ultr

Ser

ies 5000

Ser

Fig.

Angle Eyepieces.

Fig.

DERS.

a Wide

TELEXTEN

Meade Laser Collimator: The Meade Laser Collimator is an easy to use collimation device. Poor collimation can cause planetary detail to be fuzzy and star images to appear elongated or irregular. The Laser Collimator uses a red laser to accurately align the mirrors in your LightBridge Truss Tube Dobsonian telescope. Once accurately aligned, stars will appear as sharp pinpoints, planets will reveal spectacular detail, and double stars can be easily split. Simply insert the laser collimator into the eyepiece holder of the telescope, and make small adjustments to the secondary and primary mirror to center the red dot of the laser. Once centered

elescope is in collimation and ready to use.

our

More accessor telescope. To find out more about these and other accessories available for your telescope, check out the Meade General Catalog, meade.com or contact your local Meade dealer. Also check out Meade’s latest ads in Sky and Telescope and Astronom

ies will soon be available for your LightBridge Truss Tube Dobsonian

y magazine.

(800) 626-3233

www.meade.com

MEADE LIMITED WARRANTY

Every Meade telescope and telescope accessory is warranted by Meade Instruments Corporation (“Meade”) to be free of defects in materials and workmanship for a period of ONE YEAR from the date of original purchase in the U.S.A. and Canada. Meade will repair or replace a product, or part thereof, found by Meade to be defective, provided the defective part is returned to Meade, freight-prepaid, with proof of purchase. This warranty applies to the original purchaser only and is non-transferable. Meade products purchased outside North America are not included in this warranty, but are covered under separate warranties issued by Meade international distributors.

RGA Number Required: Prior to the return of any product or part, a Return Goods Authorization (RGA) number must be obtained from Meade b detailing the nature of the claimed defect, as well as the owner’s name, address, and phone number.

This warranty is not valid in cases where the product has been abused or mishandled, where unauthorized repairs have been attempted or performed, or where depreciation of the product is due to normal wear-and-tear. Meade specifically disclaims special, indirect, or consequential damages or lost profit which may result from a breach of this warranty. Any implied warranties which cannot be disclaimed are hereby limited to a term of one year from the date of original retail purchase.

This warranty gives you specific rights.You may have other rights which vary from state to state.

Meade reserves the right to change product specifications or to discontinue products without notice.

y writing, or calling (800) 626-3233. Each returned part or product must include a written statement

14-1010-48 12/05

Meade TRUSS DOBONIAN 10, LIGHT BRIDGE 8, TRUSS DOBONIAN 12, TRUSS DOBONIAN 8, LIGHT BRIDGE10 Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual