Celestron Celestar 8, Celestar Deluxe 8 Instruction Manual

INSTRUCTION MANUAL

CELESTAR

TABLE OF CONTENTS

INTRODUCTION.........................................................................................................................................5

OW TO USE THIS MANUAL

ORD OF CAUTION

A W

HE SCHMIDT-CASSEGRAIN OPTICAL SYSTEM

............................................................................................................................ 5

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

................................................................................................ 7

ASSEMBLING YOUR CELESTAR....................................................................................................... .... 8

NPACKING YOUR CELESTAR

ELESTAR DELUXE

8/C

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

SETTING UP THE TRIPOD ....................................................................................................................... 10

DJUSTING THE TRIPOD HEIGHT

.................................................................................................................... 11

ATTACHING THE WEDGE TO THE TRIPOD......................................................................................... 11

ETTING UP THE WEDGPOD

ATITUDE ADJUSTMENT

TTACHING THE CELESTAR TO THE WEDGE

NSTALLING THE FINDER

TTACHING THE FINDER BRACKET

TTACHING THE FINDER TO THE BRACKET

EMOVING THE LENS CAP

NSTALLING THE VISUAL ACCESSORIES

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

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

EDGPOD

/ W

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

................................................................................................................................13

................................................................................................................ 14

.................................................................................................... 15

............................................................................................................................. 15

......................................................................................................... 16

The Visual Back........................................................................................................................................16

The Star Diagonal..................................................................................................................................... 16

The Eyepieces ........................................................................................................................................... 17

OVING THE TELESCOPE IN

NSTALLING THE

DVANCED ASTRO MASTER SETUP

RANSPORTING YOUR CELESTAR/CELESTAR DELUXE

TORING YOUR CELESTAR/CELESTAR DELUXE

R.A. E

NCODER

AND

R.A.

DEC.................................................................................................. 18

.................................................................................................................... 18

............................................................................................................... 21

8................................................................................ 22

8 .......................................................................................... 22

TELESCOPE BASICS............................................................................................................................... 23

MAGE ORIENTATION

OCUSING

LIGNING THE FINDER

OUR FIRST LOOK

...................................................................................................................................................... 24

..................................................................................................................................... 23

................................................................................................................................... 24

......................................................................................................................................... 25

Daytime Observing................................................................................................................................... 25

Nighttime Observing................................................................................................................................. 25

ALCULATING MAGNIFICATION

ETERMINING FIELD OF VIEW

ENERAL OBSERVING HINTS

ENERAL PHOTOGRAPHY HINTS

..................................................................................................................... 26

....................................................................................................................... 27

......................................................................................................................... 27

.................................................................................................................... 28

ASTRONOMY BASICS............................................................................................................................. 29

HE CELESTIAL COORDINATE SYSTEM

OTION OF THE STARS

OLAR ALIGNMENT

.................................................................................................................................. 30

....................................................................................................................................... 31

.......................................................................................................... 29

Finding the Pole ....................................................................................................................................... 32

Latitude Scale Polar Alignment Method................................................................................................... 33

Pointing at Polaris Method of Polar Alignment....................................................................................... 33

Declination Drift Method of Polar Alignment.......................................................................................... 34

LIGNING THE

ETTING CIRCLE

RA S

.............................................................................................................. 35

USING THE CELESTAR DRIVE............................................................................................................37

OWERING UP THE DRIVE

.............................................................................................................................. 37

Celestar Manual

Outlets........................................................................................................................ ............................... 38

The Hand Controller (Optional Accessory).............................................................................................. 38

ORTHERN/SOUTHERN HEMISPHERE OPERATION

HANGING THE BATTERY

ROUBLE SHOOTING

.............................................................................................................................. 39

...................................................................................................................................... 39

......................................................................................... 39

USING THE CELESTAR DELUXE DRIVE........................................................................................... 40

POWERING UP THE DRIVE ..................................................................................................................... 40

TRACKING RATE SELECTION................................................................................................................ 41

PERIODIC ERROR CORRECTION ........................................................................................................... 41

HE HAND CONTROLLER

............................................................................................................................... 43

DECLINATION MOTOR CLUTCH ADJUSTMENT................................................................................ 43

REPLACING THE BATTERY.................................................................................................................... 44

NORTHERN/SOUTHERN HEMISPHERE OPERATION......................................................................... 45

CELESTIAL OBSERVING....................................................................................................................... 46

BSERVING THE MOON

................................................................................................................................. 46

Lunar Observing Hints ............................................................................................................................. 46

BSERVING THE PLANETS

.............................................................................................................................. 46

Planetary Observing Hints ....................................................................................................................... 46

BSERVING THE SUN

..................................................................................................................................... 47

Solar Observing Hints...............................................................................................................................47

BSERVING DEEP SKY OBJECTS

.................................................................................................................... 47

Using the Setting Circles .......................................................................................................................... 47

TAR HOPPING

EEING CONDITIONS

............................................................................................................................................... 48

...................................................................................................................................... 50

Transparency............................................................................................................................................ 50

Sky Illumination........................................................................................................................................ 50

Seeing........................................................................................................................................................ 50

CELESTIAL PHOTOGRAPHY...............................................................................................................53

HORT EXPOSURE PRIME FOCUS PHOTOGRAPHY

IGGYBACK PHOTOGRAPHY

YEPIECE PROJECTION

ONG EXPOSURE PRIME FOCUS PHOTOGRAPHY

........................................................................................................................... 54

................................................................................................................................... 56

.......................................................................................... 53

............................................................................................ 57

CCD IMAGING............................................................................................................................................60

ASTAR LENS ASSEMBLY OPTION

PIXC

ESCRIPTION OF F-NUMBERS

ASTAR CONFIGURATIONS

MAGING AT F

AMERA

CCD C

.................................................................................................................................. 60

......................................................................................................................... 61

............................................................................................................................. 61

/1.95 ........................................................................................................................................ 61

EDIUM SIZE TO SMALL GALAXIES

/6.3 (M

UNAR OR SMALL PLANETARY NEBULAE

/10 (L

LANETARY OR LUNAR

/20 (P

SING YOUR CELESTAR DELUXE TELESCOPE AT F

-- U

WITH OPTIONAL

/1.95

)................................................................................. 62

)......................................................................... 62

)....................................................................................................62

TELESCOPE MAINTENANCE............................................................................................................... 64

ARE AND CLEANING OF THE OPTICS

OLLIMATION

................................................................................................................................................ 64

............................................................................................................ 64

OPTIONAL ACCESSORIES.................................................................................................................... 66

THE MESSIER CATALOG...................................................................................................................... 73

LIST OF BRIGHT STARS........................................................................................................................ 77

Celestar Manual

TECHNICAL SPECIFICATIONS............................................................................................................78

FURTHER READING................................................................................................................ ............... 79

Celestar Manual

INTRODUCTION

Welcome to the Celestron world of amateur astronomy! For more than a quarter of a century, Celestron has provided amateur astronomers with the tools needed to explore the universe. The Celestar line of telescopes continue in this proud tradition combining large aperture optics with ease of use and portability. With a mirror diameter of 8 inches, your Celestar telescope has a light gathering power of 841 times that of the unaided human eye. Yet despite its large aperture, the Celestar optical system is extremely compact and portable because it utilizes the Schmidt-Cassegrain design. This means you can take your Celestar telescope to the mountains or desert or wherever you observe.

The Celestar telescope is made of the high e st quality materials to ensure stability and durability. All this adds up to a telescope that gives you a lifetime of pleasure with a minimal amount of maintenance. And, your Celestar telescope is versatile − it grows as your interest in astronomy grows.

Your Celestar telescope however, is not limited to astronomical usage alone. It can also be used for terrestrial viewing to study the world around you. All you need to do is take the time to familiarize yourself with your Celestron telescope and its operation.

HOW TO USE THIS MANUAL

This manual is designed to instruct you in the proper use of your Celestar telescope. The instructions are for assembly, initial use, long term operation, and maintenance. There are seven major sections to the manual. The first section covers the proper procedure for setting up your Celestar telescope. This includes setting up the tripod, attaching the telescope to the mount, balancing the telescope, etc.

The second section deals with the basics of telescope use. Topics include focusing, aligning the finder, and taking your first look. The third section deals with the basics of astronomy which includes the celestial coordinate system, the motions of the stars, and polar alignment. The fourth section deals with celestial observing covering visual observations of the planets and deep-sky objects. Using both the setting circles and star hopping are discussed. The fifth section covers celestial photography working from the easiest to the most difficult. The last major section is o n telescope maintenance, specifically on cleaning and collimation. Keeping your Celestar telescope in proper collimation is the single most important thing you can do to ensure it perfor ms well.

In addition to the major sections mentioned previously, there is a list of optional accessories for your Celestar telescope that include a brief description of its purpose. This is the section to consult when you’ve mastered the basics and ready for new, more challenging observations. The final part of this manual contains a list of objects that can be observed through your Celestar telescope. Included are the coordinates for each object, its brightness, and a code which indicates what type of an object it is. In addition, there is a list of bright stars used for aligning the setting circles.

Read the assembly instructions through completely before you attempt to set up your Celestar telescope. Then, once you’ve set up your Celestar telescope read the section on ‘Telescope Basics’ before you take it outside and use it. This will ensure that you are familiar with your telescope before you try to use it under a dark sky. Since it will take a few observing sessions to familiarize yourself with your Celestar telescope you should keep this manual handy until you have fully mastered your telescope’s operation. After that, save the manual for future reference.

Celestar Manual

A WORD OF CAUTION

Your Celestar telescope is designed to give you hours of fun and rewarding observations. There are, however, a few things to consider before using your telescope that will ensure your safety and protect your equipment.

WARNING ! NEVER LOOK DIRECTLY AT THE SUN WITH THE NAKED EYE OR WITH A TELESCOPE. PERMANENT AND IRREVERSIBLE EYE DAMAGE MAY RESULT.

NEVER USE YOUR TELESCOPE TO PROJECT AN IMAGE OF THE SUN ONTO ANY SURFACE. INTERNAL HEAT BUILD-UP CAN DAMAGE THE TELESCOPE AND/OR ANY ACCESSORIES ATTACHED TO IT.

NEVER USE AN EYEPIECE SOLAR FILTER OR A HERSCHEL WEDGE. INTERNAL HEAT BUILD-UP INSIDE THE TELESCOPE CAN CAUSE THESE DEVICES TO CRACK OR BREAK, ALLOWING UNFILTERED SUNLIGHT TO PASS THROUGH TO THE EYE.

NEVER LEAVE THE TELESCOPE UNSUPERVISED, EITHER WHEN CHILDREN ARE PRESENT OR WITH ADULTS WHO MAY NOT BE FAMILIAR WITH THE CORRECT OPERATING PROCEDURES OF YOUR TELESCOPE.

NEVER POINT YOUR TELESCOPE AT THE SUN UNLESS YOU HAVE THE PROPER SOLAR FILTER. WHEN USING YOUR TELESCOPE WITH THE CORRECT SOLAR FILTER, ALWAYS COVER THE FINDER. ALTHOUGH SMALL IN APERTURE, THIS INSTRUMENT HAS ENOUGH LIGHT GATHERING POWER TO CAUSE PERMANENT AND IRREVERSIBLE EYE DAMAGE. IN ADDITION, THE IMAGE PROJECTED BY THE FINDER IS HOT ENOUGH TO BURN SKIN OR CLOTHING.

Celestar Manual

THE SCHMIDT-CASSEGRAIN OPTICAL SYSTEM

A telescope is nothing more than an instrument that collects and focuses light. The nature of the optical design determines how the light is focused. Some telescopes, known as refractors, use lenses while others, known as reflectors, use mirrors. The Schmidt-Cassegrain optical (or Schmidt-Cass for short) system uses a combination of mirrors and lenses and is referred to as a compound or catadioptric telescope. This unique design offers large diameter optics while maintaining very short tube lengths, making them extremely portable. This makes them extremely popular among amateur astronomers. The SchmidtCassegrain system consists of a zero power corrector plate, a spherical primary mirror, and a secondary mirror. Once light rays enter the optical system, they travel the length of the optical tube three times.

Inside the optical tube you will notice a black tube (not illustrated) that extends out from the center hole in the primary mirror. This is the primary baffle tube which prevents stray light from passing through to the eyepiece or camera without striking the primary or secondary mirrors.

Figure 1-1. This cross-section diagram shows the light path of the Schmidt-Cassegrain optical system. Note that the light rays travel the length of the telescope tube three times, making this a compact design. Note that the curve of the corrector plate is greatly exaggerated

Celestar Manual

ASSEMBLING YOUR CELESTAR

The complete line of Celestar models are fork mounted telescopes with built-in single motor gear drives. The Celestar 8 and Celestar 8 computerized have a spur gear drive powered by a single 9-volt battery while the Celestar Deluxe 8 and Celestar Deluxe 8 computerized are worm gear driven powered by two 9-volt batteries. All models can also run off external AC or DC power. All come standard with the Starbright™ coating, an enhanced multilayer aluminum coating on the primary and secondary mirrors for increased reflectivity. Also, the corrector is fully coated to allow maximum light transmission.

The Celestar 8’s are shipped in two boxes. One contains the standard Wedgpod, a combination wedge and tripod. One contains the telescope with all the standard accessories, which are:

25mm SMA Ocular 1-1/4"

•

Visual Back 1-1/4"

•

Star Diagonal 1-1/4"

•

6x30mm Finder With Bracket

•

Lens Cap

•

9-volt Alkaline Battery

•

Bolt Pack

•

The Celestar Deluxe 8’s are shipped in four boxes. The telescope, the standard wedge, and the standard adjustable height tripod each are contained in its own box. And one box contains all the standard accessories, which are:

26mm Plössl Ocular 1-1/4”

•

Visual Back 1-1/4”

•

Star Diagonal 1-1/4”

•

9x50mm Finder with Bracket

•

Hand Controller with cable

•

Car Battery Adapter

•

Two 9-volt Alkaline Batteries (packaged with telescope)

•

Lens Cap (packaged with telescope)

•

Declination motor with cable (packaged with telescope)

•

In addition to the above listed accessories, the computerized models also come with standard optical encoders and an Advanced Astro Master®. This unit is installed on the fork mount and is virtually ready to use.

UNPACKING YOUR C ELESTAR 8/CELESTAR DELUXE 8

Remove the Wedgpod (or the wedge and tripod), the telescope, and the standard accessories from their respective boxes. Save the boxes since you may want to ship your telescope via a common carrier at some time in the future. To assemble the Celestar 8, you will need a 3/16” and a 5/16” Allen wrench and a Phillips screw driver.

Use the diagram on the following page (Figure 2-1, Figure 2-2) to familiarize yourself with the various parts of your Celestar telescope.

The Computerized models are identical with the exception that the Advanced Astro Master comes installed.

Assembling your Celestar8

Celestar Manual

Figure 2-1 -- Celestar 8

Figure 2-2 -- Celestar8 Deluxe

Assembling your Celestar 9

Celestar Manual

SETTING UP THE TRIPOD

(For Celestar Deluxe 8 And Celestar Deluxe 8 Computerized Only)

For maximum rigidity, the Celestron field tripod has a leg support bracket. This bracket fits snugly against the tripod legs, increasing stability while reducing vibration and flexure. However, the tripod is shipped with each arm of the leg support bracket in between the legs so the tripod legs can collapse. To set up the tripod:

1. Hold the tripod with the head up and the legs pointed toward the ground.

2. Pull the legs away from the central colum n until they will not separate any further. A sm all stop on the

top of each tripod leg presses against the tripod head to indicate maximum separation.

3. Rotate the tension knob (located underneath the support bracket on the central column) clockwise until

it is close to the bottom of the central column.

4. Turn the leg support bracket until the cups on the end of each bracket are directly underneath each leg.

Rotate the tension knob counterclockwise until the bracket is secure against the tripod legs.

Do not

over tighten.

The tripod will now stand by itself. Once the wedge and telescope are attached to the tripod, readjust the tension knob to ensure that the leg support bracket is snug. Once again, do not over tighten!

Tripod Head

Central Column

Leg Support Bracket

Tension Knob

Leg Clamp

Figure 2-3

Assembling your Celestar10

Celestar Manual

ADJUSTING THE TRIPOD HEIGHT

(For Celestar Deluxe 8 And Celestar Deluxe 8 Computerized Only)

The tripod that comes with your Celestar Deluxe 8 telescope is adjustable. To adjust the height at which the tripod stands:

1. Loosen the extension clamp on one of the tripod legs (see figure 2-3).

2. Extend the leg to the desired height.

3. Tighten the extension clamp to hold the leg in place.

4. Repeat this process for each of the remaining legs.

You can do this while the tripod legs are still folded together.

Remember that the higher the tripod legs are extended, the less stable it is. For casual observing, this may not pose a problem. However, if you plan on doing photography, the tripod should be set low to ensure stability. A recommended height is to set the tripod in such a manner that you can look directly into the eyepiece on the telescope with a diagonal while seated.

ATTACHING THE WEDGE TO THE TRIPOD

(For Celestar Deluxe 8 And Celestar Deluxe 8 Computerized Only)

Your Celestar Deluxe 8 telescope has a clock drive built into the base to track the stars as they move across the sky from east to west. However, for this drive to be useful, the telescope’s axis of rotation should be made parallel to the Earth’s axis. The wedge, which comes standard with both telescopes, allows you to tilt the telescope’s axis of rotation. This process is known as polar alignment and is described in the section by the same name. The wedge, like the tripod, is fully assembled and only needs to be attached to the tripod.

The tripod has six holes on its base for mounting equipment. Three of the holes are threaded with 5/16-18 threads and three of the holes are open. The three open holes are for mounting a different telescope in the Celestron line. To mount a wedge to the tripod, the three threaded holes are used.

To attach the wedge to the tripod:

1. Place the three slots on the wedge over the three threaded holes in the tripod head.

2. Thread the three 5/16-18x1” socket head cap screws and washers into the holes until tight (see figure

2-5)

3. Tighten the screws until the wedge cannot be moved side to side. These can be loosened later for

polar alignment.

Assembling your Celestar 11

Wedge

Threaded H oles

Tripod

Celestar Manual

Bolts

Figure 2-4

SETTING UP THE WEDGPOD

(For Celestar 8 And Celestar 8 Computerized Only)

The Wedgpod comes pre-assembled. Just remove it from the box, stand it up, and separate the tripod legs. There are stops that set the proper angle of the legs.

LATITUDE ADJUSTMENT

Before attaching the telescope to the wedge/Wedgpod, you must adjust the wedge/Wedgpod to the proper latitude. To do so:

1. Loosen the four socket head screws that hold the tilt plat in place. They are located on the side plates

of the wedge (two on each side). You’ll need a 3/16” Allen wrench.

2. Move the tilt plate until the latitude scale indicates the latitude of your observing site. The latitude

scale is on the side plate. The center of the bolt serves as the marker.

3. Tighten the socket head screws on the side p lates to hold the tilt plate in place.

You are now ready to attach the telescope to the wedge/Wedgpod.

ATTACHING THE CELESTAR TO THE WEDGE / WEDGPOD

For astronomical viewing, you should mount the telescope on the wedge/wedgpod. This will allow you to polar align the telescope, use the setting circles and the clock drive. To mount the telescope on the wedge:

Assembling your Celestar12

Celestar Manual

1. Lay the telescope on its side and locate the th r ee threaded holes in the bottom of the driv e base.

2. Partially thread one of the three 3/8"-16 bolts (supplied in the bolt pack) into the hole that is opposite

the rectangular portion of the base.

3. Pick the telescope up by the fork tines and position it above the tripod. It should be oriented so that

the telescope is over the tripod with the base pointing toward the tilt plate.

4. Slide the bolt into the slot on the to p of the tilt plate.

Drive Base

3/8”-16 Bolt

Slot

Tilt Plate

Figure 2-5

1. Tighten the bolt slightly so that the bottom of the drive base is flush to the tilt plate. Do not tighten it

fully or you will not be able to move the base enough to insert the two remaining bolts. If you do not tighten the bolt at all, the drive base ma y be tilted slightly preventing the remain in g two bolts from threading straight in.

2. Move the base of the telescope until the two remaining holes in the drive base line up with the holes in

the tilt plate on the wedge.

3. Insert the screws and tighten all three com pletely.

4. There is no need to loosen these until you are ready to remove the telescope from the wedge/wedgpod.

The Celestar 8 comes with a 6x30 finderscope which has an 7° field-of-view. The Celestar Deluxe 8 comes with a 9x50 finder, which has a 5.8° field of view. The specifications for a finderscope, 6x30 or

INSTALLING THE FINDER

Assembling your Celestar 13

Celestar Manual

9x50, stand for the magnification and the aperture, in millimeters, of the scope. So, a 6x30 finder magnifies six times and has a 30mm objective lens.

To ensure that the finder and bracket are not damaged during shipping, they are not attached to the telescope at the factory. Start by removing the finder and hardware from the plastic wrapper. Included are the following:

Celestar 8

6x30mm Finderscope

•

Rubber O-Ring

•

Three Nylon Thumbscrews (10-24x1/2)

•

Two Phillips Pan Head Screws (10-24x5/8)

•

Celestar Deluxe 8

9x50mm Finderscope

•

Rubber O-Ring

•

Three Nylon Thumbscrews (10-24x1/2)

•

Two Phillips Pan Head Screws (10-24x5/8")

•

Mounting the finder is a two-step process and is the same for the Celestar 8 and the Celestar Deluxe 8. First you mount the bracket to the telescope, then mount the finder in the bracket.

ATTACHING THE FINDER BRACKET

1. Locate the two holes in the rear cell of the telescope just left of center (when looking from the back of

the tube).

2. Remove the tape covering the two holes. The tape prevents dust and moisture from entering the

optical tube before installing the finder.

3. Place the finder bracket over the holes. Orient the bracket so that the ring with the holes for the

adjustment screws is closer to the rear cell of the telescope (see Figure 2-6).

4. Thread the screws in by hand and then tighten with a Phillips screw driver.

Figure 2-6

Assembling your Celestar14

Celestar Manual

ATTACHING THE FINDER TO THE BRACKET

With the bracket firmly attached to the telescope, you are ready to attach the finder to the bracket.

1. Thread the three nylon thumb screws into the finder bracket. Tighten the screws until the h eads are

flush with the inner diameter of the brack et r in g. Do not thread them in completely or they will interfere with the placement of the finder.

2. Slide the rubber O-ring onto the back (i.e., eyepiece end) of the finder. It may need to be stretched a

little.

3. Position the O-ring on the main body of the finder so that it is toward the front (i.e., objective) end of

the finder.

4. Slide the end of the finder where the eyepiece mounts into the front of the bracket. Push it back until

the end of the finder, where the eyepiece attaches, is past the back ring of the bracket , but NOT so far that the O-Ring is snug inside the back ring.

5. Slide the O-Ring toward the back(i.e., eyepiece end) of the finder.

6. Push the finder back until the O-Ring is snug inside the back ring of the finder bracket.

7. Hand tighten the three nylon-tipped thumbscrews until snug.

To properly align the finder, please see the section on “Aligning the Finder.”

Figure 2-7

The Celestar lens cap utilizes a bayonet-type locking mechanism to hold it in place. To remove the lens cap, hold the cover firmly and rotate the outer edge 1/2" counterclockwise and pull off.

REMOVING THE LENS CAP

Assembling your Celestar 15

Celestar Manual

INSTALLING THE VISUAL ACCESSORIES

Installing the ocular and other visual accessories is the same for both the Celestar 8 and Celestar Deluxe 8.

The Visual Back

The visual back allows you to attach most visual accessories to the telescope. If you use a 1-1/4" star diagonal or if you want to insert the eyepiece into the telescope without a diagonal, then attach the visual back to the rear cell on the back of the telescope (see Figure 2-8). To attach the visual back:

1. Remove the protective cap from the back of your telescope. It is pressed onto the rear cell.

2. Place the slip ring on the visual back over the threads on the rear cell.

3. Tighten by rotating the slip ring clockwise until tight.

Once this is done, you are ready to attach other accessories such as eyepieces, and diagonal prisms. If you want to remove the visual back, rotate the slip ring counterclockwise until it is free of the rear cell.

Figure 2-8

2. Slide the chrome portion of the star diagonal into the visual back.

The Star Diagonal

The star diagonal is a prism that diverts the light at a right angle from the light path of the telescope. For astronomical observing, this allows you to observe in positions that are more comfortable than if you were to look straight through. To attach the star diagonal:

1. Turn the thumbscrew on the visual back until its tip no longer extends into (i.e., obstructs) the inner diameter of the visual back.

3. Tighten the thumbscrew on the visual back to hold the star diagonal in place.

If you wish to change the orientation of the star diagonal, loosen the thumbscrew on the visual back until the diagonal rotates freely. Rotate the diagonal to the desired position and tighten the thumbscrew.

Assembling your Celestar16

Celestar Manual

The Eyepieces

The eyepiece, or ocular, is the optical element that magnifies the image focused by the telescope. The eyepiece fits either into the visual back directly or into the star diagonal. To install an eyepiece:

1. Loosen the thumbscrew on the star diagonal

2. Slide the chrome portion of the eyepiece into

3. Tighten the thumbscrew on the diagonal to

so that it does not obstruct the inner diameter of the eyepiece end of the diagonal.

the star diagonal.

hold the eyepiece in place.

Figure 2-9

To remove the eyepiece, loosen the thumbscrew on the star diagonal and slide the eyepiece out.

In addition to barrel diameter, eyepieces are also referred to in terms of their focal length. The focal length of each eyepiece is printed on the eyepiece barrel. The longer the focal length (i.e., the larger the number), the lower the eyepiece power and the shorter the focal length (i.e., the smaller the number), the higher the magnification. Generally, you will use low-to-moderate power when viewing. For more information on how to determine power, see the section on “Calculating Magnification.”

Barrel diameter is the diameter of the barrel that slides into the star diagonal. Standard barrel diameters are .96”, 1.25”, and 2”. The Celestar 8 and Celestar Deluxe 8 come standard for use with 1.25” barrel eyepieces.

Assembling your Celestar 17

Celestar Manual

MOVING THE TELESCOPE IN R.A. AND DEC

Pointing the telescope is done by moving the telescope in right ascension, or R.A. for short, and declination, or DEC for short (see Figure 2-11). Right ascension corresponds to east/west movement while declination corresponds to north/south movement. To make considerable directional changes:

1. Loosen the R.A. and DEC clamps on the mount.

2. Move the telescope until pointing in the desired direction.

3. Lock the R.A. and DEC clamps to hold the telescope in place.

For fine adjustment in declinatio n, simply turn the declination slow motion knob. The DEC clamp does NOT have to be loosened. Once you have the desired target, stop rotating the DEC slow motion knob. If the DEC slow motion knob will not turn, the DEC travel arm may have reached the end of the threaded rod. To correct this, rotate the DEC slow motion knob in the opposite direction until the travel arm is in the center of the fork tine (see figure 2-10). Release the DEC clamp and manually center the object you were looking at. Tighten the DEC clamp and the DEC slow motion knob will again allow fine adjustments in both directions. The Celestar Deluxe is equipped with a standard

Figure 2-10

DEC motor for vibration fr ee fine adjustment. Refer to the section “

Using The Celestar Deluxe Drive

” in this manual for infor mation on

operation and maintenance of the DEC motor.

For fine adjustments in right ascension, release the R.A. clamp until the R.A. slow motion knob rotates freely. Turn the R.A. slow motion knob until the desired object is centered. Once centered, tighten the R.A. clamp by turning it clockwise. The clamp must be sufficiently locked for the drive motors to engage and move the telescope.

WARNING: DO NOT TURN THE R.A. SLOW MOTION KNOB WHEN THE R.A. CLAMP IS IN THE FULLY LOCKED POSITION. DO NOT FORCE THE FORK MOUNT TO SWIVEL WHEN THE R.A. CLAMP IS FULLY ENGAGED.

The telescope comes equipped with setting circles to help you locate objects in the night sky. The DEC setting circle is in degree increments while the R.A. setting circle is in hour and minute increments with a marker every five minutes. The numbers on the inner circle are for the northern hemisphere while those on the outer circle are for the southern hemisphere.

INSTALLING THE R.A. ENCODER

(Celestar 8 Computerized and

Celestar Deluxe 8 Computerized Only)

The Celestar 8 Computerized and the Celestar Deluxe 8 Computerized are identical to the Celestar 8 and the Celestar Deluxe 8 with the

Figure 2-11

exception that they comes with the Advanced Astro Master attached. The Advanced Astro Master is fully installed and tested at the factory. The R.A. encoder is removed in order for the telescope to be placed in

Assembling your Celestar18

Celestar Manual

the storage position. Here is how to install the R.A. encoder (please refer to Figure 2-12 and Figure 2-13 for all installation procedur es):

1. Swing the telescope through the fork tines so that it is pointing straight up.

2. Slide the R.A. encoder shaft through the hole in the R.A. encoder bracket (i.e., the long, flat bracket).

3. Place the lock washer and nut over the encod er sh aft and tighten fully. This will hold the encoder to the bracket.

4. Slide the R.A. encoder shaft into the R.A. encoder coupling screw (Celestar 8) or the hollow bolt (Celestar Deluxe 8). Tighten the #6-32x5/16" socket set screw on the side of the R.A. encoder coupling screw/hollow bolt to hold the R.A. encoder shaft in place.

5. For the Celestar Deluxe 8, place the slotted end of the R.A. bracket over the threaded cylindrical spacer and insert the 8-32x1/4” screw into the threaded cylindrical spacer. Tighten the screw to hold the bracket in place (refer to figure 2-12).

R.A. Encoder

8-32 Phillips Pan

R.A. Encoder Bracket

Head Screw

R.A. Encoder Nut

Washer

Hollow Bolt

6-32 Socket Set Screw

Spacer

Figure 2-12

6. For the Celestar 8, place the slotted end of the R.A. bracket over the hollow cylindrical spacer and insert the 8-32x1” screw through the spacer and thread it into the threaded hole on the fork. Tighten the screw to hold the bracket in place (refer to Figure 2-13).

Assembling your Celestar 19

Celestar Manual

8-32 Phillips Pan Head

Spacer

R.A. Encoder

Encoder Bracket

Encoder Lock Nut

Knurled R.A. Coupling Screw

6-32 Socket Set Screw

Washer

Figure 2-13

The installation of the R.A. encoder of th e Advanced Astro Master is now complete. Keep in mind that th e R.A. encoder must be removed when returning the telescope to the storage position. Now connect the blue connector on the cable to the five pins on the R.A. encoder, plug the phone jack type connector to the Advanced Astro Master module, and the telescope is ready for hours of observing fun.

Please see the Advanced Astro Master instruction manual for complete operational information.

Assembling your Celestar20

Celestar Manual

ADVANCED ASTRO MASTER SETUP

(For Celestar 8 Computerized and Celestar Deluxe 8 Computerized Only)

(See the Advanced Astro Master manual for complete directions)

Once the Advanced Astro Master (AAM) is attached to the telescope, there are a few steps that need to be taken to make sure the AAM is set up for the Celestar 8. Although the AAM should already be set up for the Celestar 8, it is good practice to check and to familiarize yourself with the navigation process of the AAM.

To setup the AAM, follow these steps:

1. Roughly polar align the telescope as explained in “Latitude Scale Polar Alignment Method” of the “Polar Alignment” section of the chapter, “Astronomy Basics”.

2. Attach the AAM to the telescope.

3. Turn on the AAM.

4. The screen should read, “SET DEC = 0”. Set the telescope’s declination to 0º (see the section, “Telescope Basics”). Hit enter.

5. The AAM screen should read “MODE ALIGN STAR”. Press the down arrow once to scroll to the “MODE SETUP” screen.

6. Press enter. Use the up/down arrow to scroll to the appropriate mount. For a roughly aligned fork mount, (i.e. , the Celestar 8 Computerized) set the mount type to “EQ”. Press enter. (If you are accurately polar aligned then set the mount as “EP”.)

7. Press enter at the “SCROLL 5” window.

8. At the Chart screen, select SA or UA. This defines what ref er e nce numbers will be applied to the stars. The star reference numbers will either match those of the Star Atlas 2000 (SA) or Uranometria 2000 (UA). Hit enter.

9. In the next screen, you will set the encoder ratios and polarities. AZ should be set at -4000. Hit enter to scroll the cursor through each number and use the up/down arrows to set the numbers. AL should be set to +2160.

The AAM is now set up for the telescope. Steps 5 through 8 should already be set by the factory, so you may not have had to change anything. To use the AAM, you need to align the computer to the sky by using the “MODE ALIGN STAR” screen. Refer to the AAM manual f or complete instructions.

Assembling your Celestar 21

Celestar Manual

TRANSPORTING YOUR CELESTAR/CELESTAR DELUXE 8

You may leave your Celestar/Celestar Deluxe 8 fully set up in the house and carry it outside for a casual observing session. However, since the telescope is large and somewhat heavy on the tripod, you may want to remove the telescope and drive from the Wedgpod or tripod/wedge when moving it. To do so:

1. Remove the two lower bolts that hold the drive base to the tilt plate of the wedge or Wedgpod.

2. Partially loosen the top bolt that ho lds the drive base to the tilt plate by rotating it appr oximately half a turn.

3. Hold the telescope by the fork arms and slide it up, off the wedge/Wedgpod.

The Wedgpod can now be carried outside and the telescope reattached. For the Celestar Deluxe, since the wedge does not interfere with the tripod at all, it can be left in place once firmly attached. This holds true even if you are transporting your telescope to a remote dark site observing location. The tripod legs can be collapsed and folded back together with the wedge in place.

However, if you are planning a trip to a remote site, you should remove the telescope from the wedgpod or tripod/wedge, and return it to its box. The tripod/wedgpod legs can be transported with its legs folded back together.

STORING YOUR CELESTAR/CELESTAR DELUXE 8

When not in use, all lens and eyepiece covers should be put back in place. This will reduce the amount of dust build-up on all optical surfaces and reduce the number of times you need to clean your instrument. You may want to return everything to its original shipping container and store it there. If this is the case, all optical surfaces should be covered to prevent dust build-up.

Assembling your Celestar22

Celestar Manual

TELESCOPE BASICS

Once your telescope is fully assembled, you are ready for your first look. This section deals with some of the basics of telescope operation.

IMAGE ORIENTATION

The image orientation changes depending on how the eyepiece is inserted into the telescope. When using the star diagonal, the image is right-side-up, but reversed from left-to-right (i.e., reverted). If inserting the eyepiece directly into the visual back (i.e., without the star diagonal), the image is upside-down and reversed from left-to-right (i.e., inverted). This is normal for the Schmidt-Cassegrain design. These orientations apply to the telescope’s finder as well.

Figure 3-1

Telescope Basics

Celestar Manual

FOCUSING

The Celestar 8 focusing mechanism controls the primary mirror which is mounted on a ring that slides back and forth on the primary baffle tube. The focusing knob, which moves the primary mirror, is on the rear cell of the telescope just right of the star diagonal and eyepiece. Turn the focusing knob until the image is sharp. If the knob will not turn, it has reached the end of its travel on the focusing mechanism. Turn the knob in the opposite direction until the image is sharp. Once an image is in focus, turn the knob clockwise to focus on a closer object and counterclockwise for a more distant object. A single turn of the focusing knob moves the primary mirror only slightly. Therefore, it will take many turns (about 40) to go from close focus (approximately 25 feet) to infinity.

For astronomical viewing, out of focus star images are very diffuse, making them difficult to see. If you turn the focus knob too quickly, you can go right through focus without seeing the image. To avoid this problem, your first astronomical target should be a bright object (like the Moon or a planet) so that the image is visible even when out of focus.

Critical focusing is best accomplished when the focusing knob is turned in such a manner that the mirror moves against the pull of gravity. In doing so, any mirror shift is minimized. For astronomical observing, both visually and photographically, this is done by turning the focus knob counterclockwise.

ALIGNING THE FINDER

The Celestar 8 comes with a 6x30mm finder (9x50mm for Celestar Deluxe 8) which helps you aim the main telescope at distant objects that would be hard to find in the narrow field of the main optics. The first number used to describe the finder is the power or magnification while the second number is the diameter of the objective lens in millimeters. For example, the Celestar 8 finder is a 6x30. This means it is 6 power and has a 30mm objective lens. Incidentally, power is always compared to the unaided human eye. So a 6 power finder magnifies images six tim es more than the human eye. To make the align ment process a little easier, you should perform this task in the daytime when it is easier to locate objects in the telescope without the finder. To align the finder:

1. Choose a conspicuous object that is in excess of one mile away. This will eliminate any possible parallax effect between the telescope and the finder.

2. Point your telescope at the object you selected and center it in the main optics of the telescope.

3. Lock the R.A. and DEC clamps to hold the telescope in place.

4. Check the finder to see where the object is located in the field of view.

5. Adjust the black thumb screws on th e f inder bracket, tightening one while loosenin g another, until the cross hairs are centered on the target.

6. Tighten each black thumb screw a quarter of a turn to ensure that they will not come loose easily.

The image orientation through the finder is inverted (i.e., upside down and reversed from left-to-right). Because of this, it may take a few minutes to familiarize yourself with the directional change each screw has on the finder.

Telescope Basics

Celestar Manual

YOUR FIRST LOOK

With the telescope fully assembled and all the accessories attached, you are ready for your first look. Your first look should be done in the daytime when it is easier to locate the locking clamps and slow motion knobs. This will help to familiarize you with your Celestar 8, thus making it easier to use at night.

Daytime Observing

As mentioned in the introduction, your Celestron Celestar telescope works well as a terrestrial spotting scope. When not used to examine objects in the night sky, it can be used to study objects here on Earth.

WARNING ! NEVER POINT YOUR TELESCOPE AT THE SUN UNLESS YOU HAVE THE PROPER SOLAR FILTER. PERMANENT AND IRREVERSIBLE EYE DAMAGE MAY RESULT AS WELL AS DAMAGE TO YOUR TELESCOPE. ALSO, NEVER LEAVE YOUR TELESCOPE UNATTENDED DURING A DAYTIME OBSERVING SESSION, ESPECIALLY WHEN CHILDREN ARE PRESENT.

1. Find a distant object that is fairly bright.

2. Insert a low power eyepiece (i.e. one with a long focal length 25mm) into the telescope.

3. Release the R.A. and DEC clamps and point the telescope in the direction of the object you selected.

4. Locate the object in your finder.

5. Move the telescope by hand un til the object is centered in the finder.

6. Lock the R.A. and DEC clamps to hold the telescope in place.

7. Look through the main optics and the object will be there (if you aligned the finder first).

8. Use the slow motion knobs to center the object if needed. Remember, you should not use the drive for terrestrial viewing.

Try using different optional eyepieces to see how the field changes with various magnifications.

Nighttime Observing

Looking at objects in the sky is quite different from looking at objects on Earth. For example, many objects seen in the daytime are easy to see with the naked eye and can be located in the telescope by using landmarks. In the night sky, many objects are not visible to the naked eye. To make things easier, you are better off starting with a bright object like the Moon or one of the planets. Here is a quick description to get you started. A more detailed description is found under the section on “Visual Observing.”

1. Orient the telescope so that the polar axis is pointing as close to true north as possible. (The fork arms indicate which direction the polar axis is pointing.) You can use a land mark that you know faces north to get you in the general direction.

2. If you are observing with the Celestar 8, shim the Wedgpod legs until the mount is leveled. If you are using the Celestar Deluxe 8, extend or retract each of the three tripod legs until it is at your preferred height and the mount is leveled.

Telescope Basics

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Celestron Celestar 8, Celestar Deluxe 8 Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual