Meade DS-114AT User Manual
Instruction Manual
DS-114AT
Reflecting T elescope
Meade Instruments Corporation
Reflecting T elescopes use a concave primary mirror to collect light
and form an image. In the Newtonian type of reflector, light is reflected by a small, flat secondary mirror to the side of the main tube for
observation of the image. Light is collected by a concave mirror and
brought to a focus at F.
Reflecting Telescope
Secondary
Mirror
Concave
Mirror
F
Eyepiece
Quick-Start Guide .......................................................... 4
Telescope Features ...................................................... 7
Autostar Features .......................................................... 8
Getting Started ..............................................................10
Packing List ..............................................................10
How to Assemble Your Telescope ............................10
Some Notes About the Dual-Motor System..............11
The Viewfinder..........................................................11
Focusing the Viewfinder......................................11
Aligning the Viewfinder........................................12
Choosing an Eyepiece ............................................12
The Barlow Lens......................................................12
Observing ......................................................................13
Observing by Moving the Telescope Manually ........13
Terrestrial Observing ................................................13
Observing Using Autostar's Arrow Keys ..................13
Slew Speeds ............................................................14
Observe the Moon ....................................................14
Astronomical Observing............................................14
Tracking an Object Automatically..............................14
Alt/Az Home Position ..........................................15
Moving Through Autostar’s Menus......................15
Initializing Autostar ..............................................15
Training the Drive................................................16
Observe a Star Using Automatic Tracking ..........17
Easy (Two-Star) Align ..............................................17
Two-Star Alt/Az Alignment ........................................18
One-Star Alt/Az Alignment ........................................18
Go To Saturn ............................................................19
Take a Guided Tour ..................................................19
Basic Autostar Operation................................................20
Autostar Navigation Exercise....................................20
Entering Numbers and Text into Autostar ................21
Navigating Autostar ..................................................21
Adjusting the Speed of a Scrolling Message............21
Menus and Menu Options..............................................22
Complete Autostar Menu Structure ..........................22
Object Menu..............................................................22
Event Menu ..............................................................23
Glossary Menu..........................................................24
Utilities Menu ............................................................24
Setup Menu ..............................................................25
Caring for Your Telescope ............................................28
Collimation ................................................................28
Specifications............................................................30
Optional Accessories......................................................31
Meade Customer Service ........................................31
Appendix A: Locating the Celestial Pole........................32
Appendix B: To Find Objects Not in the Database ........33
Appendix C: Observing Satellites ..................................34
Basic Astronomy ............................................................35
CONTENTS
WARNING!
Never use a Meade®DS-114A T T elescope
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 viewfinder
at or near the Sun. Do not look through the
telescope or its viewfinder as it is moving.
Children should always have adult supervision while observing.
CAUTION:
Use care to install batteries as indicated by
the battery compartment. Follow battery
manufacturer's precautions. Do not install
batteries backward or mix new and used batteries. Do not mix battery types. If these precautions are not followed, batteries may
explode, catch fire, or leak. Improperly
installed batteries void your Meade warranty.
If you are anxious to use your DS-114AT
Telescope for the first time, before a
thorough reading of this instruction manual, see the QUICK-START GUIDE on page 4.
3
® The name “Meade” and the Meade logo are
trademarks registered with the U.S. Patent Office
and in principal countries throughout the world. All
rights reserved.
© 2001 Meade Instruments Corporation.
4
QUICK-START GUIDE
1. Remove the optical tube and tripod from the gift-
box.
Perform this setup on a flat, stable surface. It is recommended that you perform this operation in the daytime or in bright light the first time you assemble the telescope.
The optical tube assembly is shipped with the cradle
rings, yoke mount, and tripod attached. Carefully
remove the assembly from the box. Lay the assembly
on the floor.
2. Remove the optical tube from the mount.
The optical tube is shipped oriented the wrong direction
in the yoke mount for observing—you must remove the
tube from the mount and turn it around 180°.
Loosen the cradle ring lock knobs and move the knobs
out of the way so that you can open the cradle rings.
Once the rings are open, remove the optical tube from
the cradle rings.
3. Stand the tripod and orient the cradle rings.
Stand the tripod on a flat surface and gently pull the
legs apart to a fully open position. Turn the cradle rings
so that the ring base is horizontal (parallel) to the
ground. Tighten the alt lock (A) to a firm feel, so the
rings remain in that position.
This Quick Start procedure explains how to set up your DS-114AT for manual viewing. If you wish to make observations
using the Autostar handbox, please turn to
HOW TO ASSEMBLE YOUR TELESCOPE, page 10 and take the time and care
necessary to assemble all the components that are supplied with this telescope.
2
1
3
A
5
6. Adjust tripod.
Adjust the height of the tripod by lifting the clip on each
leg and extending the sliding inner section of each tripod leg to the desired length. Then press the clip back
against the leg to lock in place.
4. Attach and balance the optical tube.
Turn the optical tube around and replace it into the cra-
dle rings. Fasten the cradle rings lock knobs so that
they only hold the optical tube loosely; do not tighten
the lock knobs yet. Note the optical tube's and the
yoke's orientation in photo.
Slide the tube back and forth until you find a position
where the tube remains horizontal (i.e., without tipping
up or down). Then tighten the cradle rings lock knobs to
a firm feel.
7. Sight along the tube.
Sight along the side of the telescope's main tube to
locate an object and then observe through the eyepiece.
5. Insert the eyepiece.
Remove the supplied 25mm eyepiece (B) from its con-
tainer and place it into the eyepiece holder.Tighten the
thumbscrews (C) to a firm feel only. Remove the dust
cover from the end of optical tube assembly. Use the
focus knobs (D) to bring objects into focus.
If you wish to attach the viewfinder, see page 10.
If you wish to initialize Autostar, see page 15.
If you wish to align the telescope, see page 17.
If you wish to use Autostar to automatically view
objects, see page 19 for some examples.
7
4
6
5
B
C
D
6
1
2
9
5
11
10
6
16
20
13
15
7
3
23
Fig. 1: DS-114AT Series Telescope.
Fig. 1b (Inset): Computer Control Panel.
(A) LED
(B) 12V Port
(C) Handbox Port
(D) AZ Port
(E) ALT Port
(F) AUX Port
12
14
19
18
21
4
Fig. 1c: Cradle Rings Lock
Knobs (on opposite side).
17
3
A C D E FB
8
22
7
The DS-114AT telescope has a variety of useful features. Be sure to become acquainted with
all of these controls before you begin making observations through the telescope.
Focus Knobs:
Move the telescope’s focus drawtube in a finely-controlled motion
to achieve
precise image focus.
Eyepiece Holder: Holds the eyepiece in place.
Eyepiece Holder Thumbscrews (2): Tighten the eyepiece in place. T ighten to a firm feel only .
Eyepiece: Place one of the supplied eyepieces into the eyepiece holder (2, Fig. 1).
Viewfinder: Provides an easier way to initially sight objects than the main telescope eyepiece
which has a narrower field of view.
Viewfinder Alignment Screws (4): Adjust these screws to align the viewfinder.
Viewfinder Alignment Bracket: Attaches the viewfinder to the telescope (11, Fig. 1).
Alt Indicator: Displays the angle (in degrees) of the altitude of the optical tube.
Cradle Rings (2): Hold optical tube securely in place.
Cradle Ring Lock Knobs (2): Tighten to a firm feel to hold the optical tube securely in
place. Fig. 1c depicts a cradle ring clamped in place by one of the lock knobs and one of
the lock knobs hanging loose.
Optical Tube: The main optical component that gathers the light from distant objects and
brings this light to a focus for observation with the eyepiece.
Primary Mirror Cell: Contains the optical tube's primary mirror and 3 screws that are used
in a collimation adjustment. Note: Do not remove the piece of felt from the cell.
Alt (Vertical) Gear and Motor: Moves the telescope along the vertical axis.
Battery Pack: Supplies power to the assembly. Install 10 user-supplied AA batteries.
Autostar: Autostar is able to control nearly all the functions of the telescope.
Tripod Legs: To use, spread the legs as far as they will open. Adjust the height of the tri-
pod by lifting the clip on each leg and extending the sliding inner section of each tripod leg
to the desired length. Then press the clip back against the leg to lock in place.
Accessory Tray: Conveniently holds extra eyepieces, Autostar, and other accessories.
Az (Horizontal) Gear and Motor: Moves the telescope along the horizontal axis.
Az Lock: Controls the manual horizontal movement of the telescope. Turning the Alt lock
counterclockwise unlocks the telescope enabling it to be freely moved by hand on the horizontal axis. Turning the Alt lock clockwise (to a firm feel only) prevents the telescope from
being moved manually and engages the vertical motor drive clutch for Autostar operation.
Computer Control Panel (Fig. 1b)
A. LED: The red power indicator light illuminates when power (i.e., the battery pack)
is supplied to the Autostar handbox and to the telescope’s motor drive.
B.
12V: Plug the battery pack into this port.
C. Handbox (HBX) Port: Plug the #494 Autostar handboxinto this port.
D. Azimuth (AZ) Port: Plug the Az motor into this port.
E. Altitude (ALT) Port: Plug the Alt motor into this port.
F. Auxiliary (AUX) Port:
Provides connection for Meade accessories.
Yoke Mount: Along with the cradle rings, holds the optical tube assembly (11, Fig. 1).
Alt Lock: Controls the manual vertical movement of the telescope. Turning the Alt lock
counterclockwise unlocks the telescope enabling it to be freely tilted by hand on the vertical axis. Turning the Alt lock clockwise (to a firm feel only) prevents the telescope from
being moved manually and engages the vertical motor drive clutch for Autostar operation.
Dust Cap: Pull to remove the dust cap from the front lens of the telescope.
Note: The dust cap should be replaced and the power turned off to the telescope
after each observing session. Verify that any dew that might have collected during
the observing session has evaporated prior to replacing the dust cap.
TELESCOPE FEATURES
Want to learn
more about the
viewfinder?
See pages 10
through 12.
Want to learn
more about
collimation?
See pages 29
and 30.
21
22
23
Want to learn
more about
Autostar's
buttons?
See pages 8
and 9.
Autostar's
menus?
See pages 22
through 27.
8
Control of the DS-114AT Series Telescopes is through
the operation of the #494 Autostar handbox. Nearly all
functions of the telescope can be operated with just a
few pushes of Autostar’s buttons. Some of the major
features of Autostar are:
■ Automatically move the telescope to any of the
1400 objects stored in the database or manually
enter the astronomical coordinates of any celestial
object.
■ Take a guided tour of the best celestial objects to
view on any given night of the year.
■ Access a glossary of astronomical terms.
■ Calculate which eyepiece to use for optimum view-
ing of a celestial object.
Autostar has soft-touch keys and the LCD (Liquid
Crystal Display) is backlit with a red LED (Light
Emitting Diode) for easy viewing in the dark.
NOTE: Autostar does not require batteries; the
telescope’s batteries supply power to Autostar.
2-Line LCD: Displays Autostar menu and help information.
• Top line: Displays the menu or category name.
• Bottom line: Displays a menu option or information about a subject.
ENTER Key: When an option is displayed, press ENTER to enable the choice. When a
menu is displayed, press ENTER to access the next menu or data level in the Autostar
database. ENTER is similar to the RETURN key on a computer. See
MOVING THROUGH
AUTOSTAR'S MENUS, page 15 and MENUS AND MENU OPTIONS, page 22.
NOTE: If ENTER is pressed for two seconds or more and then released, Autostar
emits a beep and “ENTER to Sync” is displayed. If the "ENTER to Sync" feature is
accessed by mistake, press MODE to return to the previous screen. See
HIGH
PRECISION, page 26, for more details about this feature.
MODE Key: When a menu is displayed, press MODE to return to the previous menu or data
level in the Autostar database. MODE is similar to the ESCAPE key on a computer.
NOTE: Pressing MODE while in the “Select Item” level moves Autostar to the topmost screen: “Select Item: Object.”
NOTE: If MODE is pressed and held for two seconds or more, the following information is then available using the Scroll keys (6 and 7, Fig. 2):
• Right Ascension and Declination (astronomical) coordinates
• Altitude (vertical) and Azimuth (horizontal) coordinates
• Local Time and Local Sidereal Time (LST)
• Timer and Alarm Status
Press MODE again to return to the previous menu.
GO TO Key: Moves the telescope to the currently selected object. While the telescope is
moving, the operation may be aborted at any time by pressing any key except GO TO.
Pressing GO TO again resumes the operation.
The GO TO key also allows you to perform a "spiral search." Aspiral search is useful when
the telescope is commanded to go to an object, but that object is not visible in the eyepiece
after the telescope finishes its search. (This sometimes occurs during the alignment procedure.) Press GO TO when the slew is finished and the telescope starts slewing in a spiral pattern at a very slow speed around the search area. Look through the eyepiece and
when the object does become visible, press MODE to stop the spiral search. Then use the
Arrow keys to center the object.
Fig. 2: #494 Autostar Handbox.
AUTOSTAR FEATURES
DEFINITION:
Throughout this manual, you will notice
the term "Alt/Az."
Alt/Az is frequently
used to refer to
Altitude (vertical) and
Azimuth (horizontal).
Alt/Az is just one of
many methods used
by amateur
astronomers to help
locate stars in the
night sky.
TIP: When a message is scrolling
across the display,
press and hold the Up
Arrow key to increase
the scrolling speed or
press and hold the
Down Arrow key to
decrease the scrolling
speed.
9
Arrow Keys: Move the telescope in a specific direction (up, down, left, and right), at any
one of nine different slew speeds.
The Arrow Keys can also be used to scroll through the letters of the alphabet and numeri-
cal digits. The Down Arrow key starts with the letter "A" and the Up Arrow key starts with
the digit "9." The Left and Right Arrow keys moves the cursor left and right across the LCD
display.
, Scroll Keys: Access options of the menu displayed on the top line of the screen.
Options within the menu are displayed, one at a time, on the second line. Press the Scroll
keys to move through the options. Press and hold a Scroll key to move quickly through the
options, or to change scroll speeds of text.
The Scroll keys also scroll through the letters of the alphabet and numerical digits.
Tip: When a message is scrolling across the display, press and hold the Up Scroll
key to increase the scrolling speed, or press and hold the Down Scroll key to
decrease the scrolling speed.
NOTE: The Scroll Down key and the Down Arrow key move forward through the
alphabet & digits (A to Z, 0 to 9). The Scroll Up key and the Up Arrow key move
backward (Z to A, 9 to 0).Common symbols are also available in the list.
Speed/? Key: Press the Speed/? key to cycle through the nine slew speeds that move the
telescope. Each time the Speed/? key is briefly pressed, the current speed will be shown
for about two seconds on the display.
The Speed/? key also accesses the "Help" file. "Help" provides on-screen information for
whatever task is currently active.
NOTE: Pressing the Speed/? key very briefly changes the slew speed. Holding
down the Speed/? key longer (one to two seconds) accesses the Help function.
If you have a question about an
Autostar operation (e.g., INITIALIZATION, ALIGNMENT, etc.), hold down
the Speed/? key and follow the directions that scroll on the second line of
the LCD screen. When a word appears
in [brackets], press ENTER to access
the Autostar Glossary. A definition or
more detailed information is displayed.
Press MODE to return to the scrolling
Autostar Help display.
When satisfied with the Help provided,
press MODE to return to the original
screen and continue with the chosen
procedure.
Coil Cord: Plug the Autostar coil cord
into the HBX port (C, Fig. 1b) of the
computer control panel.
Join an Astronomy Club
Attend a Star Party
A fun way to learn more about astronomy is to
join an astronomy club. Check your local newspaper, school, library, or telescope dealer to find
out if there’s a club in your area.
At club meetings, you will meet other astronomy
enthusiasts with whom you will be able to share
your discoveries. Clubs are an excellent way to
learn more about observing the sky, to find out
where the best observing sites are, and to compare notes about telescopes, eyepieces, filters,
tripods, and so forth.
Often, club members are excellent astrophotographers. Not only will you be able to study
examples of their art, but you may even be able
to pick up some “tricks of the trade” to try out on
your DS-114AT telescope.
Many groups hold regularly scheduled star parties at which you can observe with many different telescopes and examine other pieces of
astronomical equipment. Magazines such as
Sky & Telescope and Astronomy print schedules
for many popular star parties around the United
States and Canada.
Want to learn
more about
slew speeds?
See page 14.
10
Packing List
Assembling the telescope for the first time requires only a few minutes. When first opening the
packing box, note carefully the parts listed on your giftbox.
How to Assemble Your Telescope
The telescope attaches directly to the tripod. The telescope in this way is "mounted" in an
“Altazimuth” (“Altitude-Azimuth,” or “vertical-horizontal”) format. The telescope mounted this way
moves along the vertical and horizontal axes, corresponding to the astronomical axes known as
Declination (vertical) and Right Ascension (horizontal).
Perform this setup on a flat, stable surface. It is recommended that you perform this operation
in the daytime or in bright light the first time you assemble the telescope.
1. Remove the optical tube and tripod from the giftbox: The optical tube assembly is
shipped with the cradle rings (9, Fig. 1), yoke mount (21, Fig. 1), and tripod attached.
Carefully remove the assembly from the box. Lay the assembly on the floor.
2. Remove the optical tube from the mount: The optical tube (11, Fig. 1) is shipped oriented the wrong direction in the yoke mount for observing—you must remove the tube from
the mount and turn it around 180°.
Loosen and unlatch the cradle ring lock knobs (10, Fig. 1) so that you can open the cradle
rings (9, Fig. 1). Once the rings are open, remove the optical tube from the cradle rings.
Carefully note the orientation of the tube, so that you can rotate it 180° later on when you
replace it in the rings.
3. Stand the tripod and adjust the cradle rings: Stand the tripod on a flat surface and gently pull the legs (16, Fig. 1) apart to a fully open position. Turn the cradle rings so that the
cradle ring base is horizontal (parallel) to the ground. Tighten the alt lock (22, Fig. 1), so
the rings remain in the horizontal position.
4. Attach the utility tray to the tripod: Place one of the tray's flanges around one edge of a
tripod leg and then pull the tray around until the other flange snaps in place (Fig. 5). The
utility tray (17, Fig. 1) can be pushed up or down the tripod leg to a convenient height.
5. Attach and balance the optical tube:Turn the optical tube around 180° and replace it into
the cradle rings. Fasten the cradle rings lock knobs (10, Fig. 1) so that they only hold the
optical tube loosely; do not tighten the lock knobs yet.
Slide the tube back and forth until you find a position where the tube remains horizontal
(i.e., without tipping up or down). Then tighten the cradle rings lock knobs to a firm feel.
6. Attach the Alt (vertical) motor to the Alt gear:Place the knurled ring of the motor assem-
bly over the Alt gear. Note that three small plastic tabs project outwards from the face of
the gear (Fig. 7). These "locator" tabs fit into the mating slots inside the knurled ring.
Wiggle the motor assembly over the gear assembly until the motor slips into place. Thread
the knurled ring over the mating threads of the gear assembly to lock the motor. See Fig.
8. Tighten to a firm feel only.
7. Attach the Az (horizontal) motor to the Az gear: Attach the Az motor assembly to the
the Az gear using the procedure described in step 6. See Fig. 9.
8. Connect the motor assembly cords: Plug the cord from the alt motor assembly into the Alt
port (E, Fig.1b) of the computer control panel. Plug the cord from the az motor assembly into
the Az port (D, Fig.1b) of the computer control panel.
9. Attach the viewfinder bracket: Use a Phillips-head screwdriver to thread the two attachment
screws in the viewfinder bracket (these screws are placed inside the bracket at the factory) into
the mating threads located on the optical tube (Fig. 10).
10. Attach the viewfinder tube: Carefully remove the rubber eyecup from the viewfinder
before sliding the viewfinder into the bracket. Then slide the viewfinder, eyepiece-end first
(the end to which the rubber cup was attached) into the viewfinder bracket. Replace the
rubber eyecup. Tighten the four alignment thumbscrews (6, Fig. 1 and Fig. 11) to a firm-
feel to hold the viewfinder in the bracket.
11. Insert the eyepiece: Remove the supplied 25mm eyepiece from its container and place it
into the eyepiece holder (2, Fig. 1). Tighten the thumbscrew (3, Fig. 1) to a firm feel only.
GETTING STARTED
Fig. 4: Adjust the cradle
rings.
Fig. 6: Attach and balance the optical tube.
Fig. 3 Remove assembly
from the giftbox.
Fig. 5 Attach tray to the
tripod:
Fig. 7: Motor (left) and
gear (right) assembly.
Note the slots and the
locator tabs.
11
12. Connect Autostar: Plug the coil cord of the Autostar Controller into the HBX port (C,
Fig.1b) of the computer control panel.
WARNING: Make sure you plug in Autostar before you plug in the battery pack.
NOTE: Autostar does not require batteries; the telescope’s batteries supply power
to Autostar.
13. Insert batteries: Install 10 AA user-supplied batteries into the battery pack (Fig.12), ori-
ented as shown on the diagram on the battery slots of the battery holder.
CAUTION: Use care to install batter ies as indicated by the battery compartment.
Follow battery manufacturer's precautions. Do not install batteries backwards or
mix new and used batteries. Do not mix battery types. If these precautions are not
followed, batteries may explode, catch fire, or leak. Improperly installed batteries
void your Meade warranty. Always remove the batteries if they are not to be used
for a long period of time.
14. Connect battery pack: Plug the battery pack into the 12V port (B, Fig.1b) of the comput-
er control panel. Attach the pack to one of the tripod legs using the Velcro fastener or set
it on the utility tray.
15. Adjust tripod: Adjust the height of the tripod to a convenient viewing height by lifting the
clip on each leg and extending the sliding inner section of the leg to the desired length.
Then press the clip back against the leg to lock in place.
15. Remove the dust cover: Pull out the dust cover (23, Fig. 1) from the optical tube.
Assembly of the telescope is now complete.
Some Notes About the Dual-Motor System
• For the motors to be operational, the Az and Alt lock-knobs (19, Fig. 1) and (22, Fig. 1)
must be in their locked positions. Firm-feel tightening of these locks is sufficient. Do not
overtighten. If these are not sufficiently tightened, Autostar may display a motor fault message.
• When setting up the telescope, always plug in the battery pack to the control panel last,
after plugging in the two motors and Autostar. Connecting the battery pack to the control
panel before the motors and Autostar are connected may result in false electrical signals
being sent to the motors, causing them to malfunction. In this case unplug the battery pack
from the control panel, wait a few seconds, and plug the battery pack back into the control
panel. This operation clears the motors of any false signals.
• T ake care that cords do not become wrapped around the telescope; keep the cords “loose”
at all times. Do not allow the telescope to slew into the tripod or other fixed object. Do not
touch or hold the telescope tube while it is moving.
• If the motors stall or do not have sufficient power to move the telescope, place fresh batteries in the battery pack. Long-life alkaline batteries are recommended.
• The first time you initialize your system, make sure you train the drives. This allows
Autostar to move the telescope precisely to objects. See page 16 for detailed infofrmation.
The Viewfinder
Because the main telescope has a fairly narrow field of view, locating objects directly in the
main telescope can sometimes be difficult. The viewfinder (5, Fig. 1) is a small, wide-field telescope with crosshairs that permits you to locate objects more easily. When the viewfinder and
optical tube are aligned to each other, both point to the same position in the sky. An object located in the viewfinder is therefore also positioned within the field of the main telescope. Before
aligning the viewfinder to the optical tube, focus the viewfinder.
Focusing the Viewfinder:
1. Turn the viewfinder eyepiece on its internal thread. Generally a few turns are sufficient to
achieve proper focus.
Fig. 9: Attach Az motor.
Fig. 11: Attach the viewfinder tube to bracket and tighten thumbscrews.
Fig. 10: Attach the viewfinder bracket to the optical
tube.
Fig. 12: Insert 10 AA batteries into battery pack.
Fig. 8: Attach Alt motor.
DEFINITION:
A capital "X" is used to
denote an eyepiece's
(or a Barlow's) power or
magnification. For example, "40X" is read as
"40-power."
12
Aligning the Viewfinder:
It is recommended that you perform steps 1 through 4 of this procedure during the daytime and
step 5 at night.
1. Loosen the Az lock (19, Fig. 1) and the Alt lock (22, Fig. 1) by turning the locks about one
turn counterclockwise, permitting the telescope to move freely on its axes.
2. If you have not already done so, place a low-power (e.g., 25mm) eyepiece in the eyepiece
holder of the main telescope (2, Fig. 1) and point the telescope at an easy-to-find land
object (e.g., the top of a telephone pole). Turn the focuser knob ( 1,Fig. 1) so that the image
is sharply focused. Center the object precisely in the main telescope’s field of view.
3. Re-tighten the Az lock (19, Fig. 1) and the Alt lock (22,Fig. 1).
4. Now, looking through the viewfinder, turn some or all of the viewfinder’s alignment screws
(6, Fig. 1) until the viewfinder’s crosshairs point precisely at the same object as centered
in the main telescope. The viewfinder is now aligned to the main telescope. The right-hand
image in Fig. 13A shows an object centered in the main telescope before the viewfinder
(the left-hand image) has been aligned to the main telescope. Fig. 13B shows these same
images after the viewfinder and main telescope are aligned.
5. Check this alignment on a celestial object, such as the Moon or a bright star, and make
any necessary refinements.
Choosing an Eyepiece
A telescope’s eyepiece magnifies the image formed by the telescope’s main optics. Each eyepiece has a focal length, expressed in millimeters, or “mm.” The smaller the focal length, the
higher the magnification. For example, an eyepiece with a focal length of 9mm has a higher
magnification than an eyepiece with a focal length of 25mm.
Your telescope comes supplied with a low-powered 25mm eyepiece which gives a wide, comfortable field of view with high image resolution.
Low power eyepieces offer a wide field of view, bright, high-contrast images, and eye relief during long observing sessions. To find an object with a telescope, always start with a lower power
eyepiece such as a 25mm. When the object is located and centered in the eyepiece, you may
wish to switch to a higher power eyepiece to enlarge the image as much as practical for prevailing seeing conditions.
NOTE: Viewing conditions vary widely from night-to-night and site-to-site.
Turbulence in the air, even on an apparently clear night, can distort images. If an
image appears fuzzy and ill-defined, back off to a lower power eyepiece for a more
well-resolved image.
The power (or magnification) of a telescope is determined by the focal length of the telescope
and the focal length of the eyepiece being used. To calculate eyepiece power, divide the telescope's focal length by the eyepiece's focal length. For example, you may wish to use a 25mm
eyepiece. Look up the focal length of the telescope under "Specifications," page 30. The focal
length is listed as 910mm.
Telescope focal length divided by Eyepiece focal length = Eyepiece power
910 25 = 37
The eyepiece power, or magnification is therefore 37X (approximately).
The Barlow Lens
Some Meade telescopes include a power multiplier called a Barlow lens. The Barlow supplied
with the DS-114AT triples the power obtained by an eyepiece alone. In the example above, a
25mm eyepiece results in 37X magnification. When used with the supplied Barlow, the telescope optics result in a 111X magnification. To use the Barlow, insert it into the eyepiece holder, followed by the eyepiece (Fig. 15).
Fig. 13: Aligning the
viewfinder.Note that objects
appear upside-down and
reversed left-for-right when
observed in the viewfinder.
Telescope
Viewfinder Eyepiece
A. Not aligned
B. Aligned
Fig. 14: Eyepiece and
focuser assembly.
Fig. 15: Eyepiece and
Barlow lens.
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