Zhumell Kepler User manual

KEPLER 152

WARNINGS
•Do not use telescope or finderscope to look at the sun without
an appropriate solar filter.
•Make sure no screws are loose before using telescope.
•Do not drop, shake, or throw your telescope as doing so may
damage the telescope or people around you.
•Objects in telescope may be farther away than they appear.
•Eyepieces intended for external use only.
•Don’t worry, be happy...
Zhumell telescopes are precision astronomical instruments de-
signed to be easy to use and versatile in their application. As with
any telescope, Zhumell telescopes require some technical knowl-
edge of stellar movement and optical properties. We have tried to
provide the basics of telescope use and astronomical viewing in
this manual. If, after reading through this manual, you still have
questions regarding the setup and use of your telescope, please
feel free to contact us at [email protected] or at (800)922-
2063. Our customer service representatives will be able to help
address any problems you are having with your Zhumell tele-
scope. We also have more information available on our website
at www.zhumell.com. Please let us know about your experiences
with your Zhumell telescope. We would like to hear your feed-
back and see your astrophotographs. Enjoy your Zhumell.
INTRODUCTION

SPECIFICATIONS
OPTICAL TUBE ASSEMBLY
Type Refractor
Objective (mm) 152
Focal Length (mm) 1200
Highest Useful Magnification 360x
Resolving Power 0.92
Limiting Magnitude (Visual) 12.8
Limiting Magnitude (Photographic) 10.8
Focal Ratio F/7.9
Eyepiece Format 1.25” or 2“
Finder Scope 8x50
Mount Type EQ5 Equitorial
MOUNT
Materials Aluminum
R.A. Adjustment Manual Worm Gear
Dec. Adjustment Manual Worm Gear
Clock Drive Axis R.A. and Dec.
Clock Drive Power 2 - 9V Batteries
INCLUDED ITEMS
•Optical Tube Assembly
•8x50 Finderscope
•EQ5 Equitorial Mount
•Adjustable Speed Clock Drive with Hand Controller
•R.A. and Dec. Adjustment Knobs
•Counterweight (2)
•Aluminum Tripod
•Accessory Tray
•6.5mm and 20mm Plossl Eyepieces
•1.25“ Image Diagonal

1. Tripod
2. Mount Assembly
3. Optical Tube Assembly
4. Eyepiece
5. Finderscope
6. Optical Tube Mounting Belt
7. Focuser
8. Image Diagonal
9. Dec. Adjustment Knob
10. Dec. Axis Release
11. Declination Scale
12. Hour Circle (R.A. Scale)
13. Polar Alignment Scope
14. Latitude Scale
15. Latitude Adjustment
16. Counterweight
17. Counterweight Shaft
TELESCO PE LEGEND
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1
3
4
5
6
7
8

CARE OF YOU RTELESCO PE
A telescope is carefully aligned during construction and great care should
be taken to maintain this alignment over the life of the telescope. Cleaning
should be done as little as possible and then only with a mild soap solution
and soft, lint-free cloth. Do not rub elements when cleaning. Blot optical
components gently and allow telescope to air dry. Store telescope in box
when not in use. Do not use alcohol or solvents to clean any parts of the
telescope. Do not remove optical elements from telescope as doing so may
affect the alignment of optical components when reassembled. If telescope
needs realignment, contact Zhumell or another professional.
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16
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14

TELESCO PE ASSEMB LY
1. Extend tripod legs to comfortable working
height and tighten wingnuts to ensure stabil-
ity. Separate tripod legs and ensure that the
legs are extended to equal heights. The top of
the tripod should be level to ensure stability
when mounting telescope.
2. Remove accessory tray mounting screw at
the center of tripod leg crossbracce. Set acces-
sory tray on crossbrace, lining us the center
hole of the accessory tray with the raised fit-
ting at the center of crossbraces. Reinsert and
tighten mounting screw.
3. Locate the mount alignment prong extend-
ing up from the north leg of the tripod (la-
belled with an N above the leg). Also locate
the mount rotational stabilization thumbscrews
below the front latitude adjustment screw.
4. Remove the mount base screw. Loosen the
mount rotational stabilization thumbscrews
enough to allow the alignment prong to be
inserted between the bases of the screws. Set
the mount on the top of the tripod so that the
tripod alignment prong is lined up between
the mount rotational stabilization screws.
Tighten rotational stabilization screws so that
the fron mount extrusion is centered over the
north tripod leg. Isert the mount base screw
through the hole in the tripod platform and
hand tighten.

6. Holding the counterweight shaft, turn the
Dec. axis cap attached to the shaft clockwise
(looking at the large end of the cap) until it
stops. Insert the shaft into the counter-weight
shaft socket and screw the shaft into the socket
unti secure. To eliminate the gap between the
Dec. axis cap and the Dec. axis of the mount,
turn cap (without turning the counterweight
shaft) until it is snug with the end of the Dec.
axis.
7. Remove screw located at the end of the
counterweight shaft. Loosen the thumbscrews
on the counterweights until shaft opening in
the counterwiegt is completely unobstructed.
With the thumbscrew pointing down, slide
the counterweight up the counterweight shaft
and tighten counterweight thumbscrew until
snug. Repeat for each counterweight. Replace
the end screw of the counterweight shaft and
tighten until snug.
5. Loosen R.A. and Dec. axes by turning axis
release levers 180°. Position mount so that
Dec. axis is at 0° and R.A. Axis is at 0, then
re-tighten the axis release levers. The mount
should now vertically level. With the mount in
this vertical position, find the counter-weight
shaft socket located at the end of the Dec. axis
above the north leg of the tripod.

8. Loosen the two thumbscrews located at the
top of the mount to allow the optical tube
mounting rings to be inserted in the groove.
Place the optical tube mounting rings into the
groove and tighten the large thumbcrew until
the end of the screw is snug against the optical
tube mounting ring base. Tighten the small
screw against the optical tube mounting ring
base to add stability to the moounting rings.
9. Open optical tube mounting rings by
loosening thumbscrews on side of mount-
ing rings. Lift the optical tube assembly by
the attached handle near the focuser and
set it into the optical tube mounting rings,
guiding it with your other hand. Close the
optical tube mounting rings and retighten the
thumbscrews on the mounting rings to secure
optical tube assembly.
10. Remove nuts from finderscope mount-
ing bolts near the focuser on the optical tube
assembly. Slide finderscope mount over the
bolts and replace nuts, turning them until they
are snug against the finderscope mount.
11. Loosen finderscope mounting screws
until finderscope can be easily slid into the
mount. Slide finderscope into the mount and
retighten mounting screws so that finderscope
is approximately aligned with the telescope.

12. To use a 1.25“ image diagonal, loosen eye-
piece receptacle thumbscrew at end of focuser.
Remove dustcover from eyepiece receptacle.
Insert chromed end of image diagonal into
the eyepiece receptacle. Re-tighten eyepiece
receptacle thumbscrew to secure image diago-
nal place desired eyepiece into the image di-
agonal and secure by tightening thumbscrew.
13. To use a 1.25“ eyepiece without the image
diagonal, loosen eyepiece receptacle thumb-
screw at end of focuser. Remove dustcover
from eyepiece receptacle. Insert chromed
end of eyepiece into the eyepiece receptacle.
Re-tighten eyepiece receptacle thumbscrew to
secure eyepiece.
13. To use a 2“ eyepiece or image diagonal,
2“-1.25“ adapter thumbscrews near the end
of the focuser. Remove the 2“-1.25“ adapter.
Insert desired 2“ image diagonal or eyepiece
and retighten thumbscrews to secure.
ASSEMB LYNOT ES
In order to avoid visible vibration when viewing at high magnification,
adjust the counterweight position on the counterweight shaft to offset the
weight of the optical tube assembly and balance the telescope.
When placing the optical tube assembly into the mounting rings, center the
rings along the length of the optical tube assembly. Centering the rings along
the length of the optical tube assembly will help to keep the telescope bal-
anced and increase overall stability of the telescope.
14. Enjoy your telescope.

CLOCK DRIVE CONTROLS
Direction and Speed
Controls
Hemisphere and Power
Setting
Battery Pack Connection
Motor Connection Cord
CONNECTING THE HAND CONTROLLER
To use the clock drive, connect the havd controller by plugging the Motor
Connection Cord into the receptacle at the base of the plastic housing on the
R.A. drive of the mount. Place 4D-cell batteries into the battery pack and
plug the power cord from the battery pack into the Battery Pack Connection
receptacle in on the hand controller. To activate the hand controller, simply
switch the hemisphere setting to the appropriate setting and press the desired
speed and direction button.

USING THE CLOCK DRIVE
The clock drive included with your telescope is designed to track the move-
ment of stars. It will help keep stars in your field of view during long periods
of viewing as long as the telescope is properly polar aligned and the clock
drive is properly used. Do not be alarmed if you turn on the clock drive and
do not see the telescope moving. Stars appear to move very slowly and the
telescope may not apear to move over a short period of time. To see if your
clock drive is working, aim the telescope at a stationary terrestrial object and
engage the clock drive. Let the clock drive run for 10 to 15 minutes. If the
object you had originally aimed the telescope at appears to have moved when
looking through the eyepiece of the telescope, the clock drive is working.
CLOCK DRIVE SETTINGS
The clock drive features two sets of controls which can be used to control
the motion of the telescope The power switch doubles as the hemisphere set-
ting. If you are using the telescope in the Northern Hemisphere, the switch
should be set to the upper position, in the Southern Hemisphere, the switch
should be set to the lower position. The speed setting should be adjusted
while viewing to help keep stars centered in the field of view. You may have
to increase or decrease your speed setting if stars appear to drift in your field
of view. You will need to adjust the clock drive based on what you are look-
ing at while viewing. As a general rule, the farther away from the celestial
pole (closer to the horizon) an object that you are viewing is, the faster it will
appear to move and the faster the clock drive speed will need to be set.
MANUAL ADJUSTMENT WITH CLOCK DRIVE
The clock drive included with your telescope should only be used to follow
stars. When you would like to point your telescope at a different celestial
object, you must disengage the clock drive. By loosening the thumbscrew
on the clock drive R.A. axis, you will disengage the clock drive, protecting
the clock drive and making manual adjustment easier. Manually adjusting the
R.A. axis with the clock drive engaged may cause the gearing in the clock
drive to strip, compromising the operation of the clock drive. When you
would like to reengage the clock drive, simply tighten the thumbscrew and
use the clock drive hand controller to begin tracking stars.

FINDERSCO PE ALIGNMENT
1. Insert the lowest power eyepiece into the eyepiece adapter. Focus eyepiece
to view an easily recognizable distant object (car license plate, sign, table,
etc.).
2. Look through finderscope being careful not to move the telescope in any
way. Adjust finderscope focus by turning the eyepiece of the finderscope
back and forth until image is in focus. Check to see if the object viewed
through the eyepiece lines up at the center of the finderscope crosshairs. If
not, then your finderscope needs to be realigned.
3. To align finderscope, loosen the thumbscrews which secure the find-
erscope slightly. Gently move finderscope to center crosshairs on object.
Tighten thumbscrews to secure finderscope in new position. This may take
some time, but will make finding astronomical objects much easier when
using your telescope.
SOM ENOT ES ONVIEWING
Never look at the sun without using a solar filter. When using a solar filter,
do not remove the full lenscap, view only through the small opening in the
lenscap. Looking at the sun without proper use of a solar filter can cause
permanent eye damage.
When looking through the telescope, the image will appear to be upside-
down and inverted. This results from the optical system design and is nor-
mal. This can be corrected by using a diagonal mirror when viewing.
Use of the finderscope will help locate celestial objects more quickly as the
finderscope has a much wider field of view than the telescope. When view-
ing, start with the lowest power magnification and work up to the desired
magnificaiton as this will simplify focusing greatly.
When viewing faint deep sky objects, images will not show color. The hu-
man eye is not able to distinguish the differences in color found in such dim
images. The lack of color is due to human anatomy, not any limitations of
telescope construction.

BEGINNING OBSERVATION
For beginning observation, the moon is one of the easiest and most enjoy-
able objects to view. You can acquaint yourself with the movements of the
telescope by simply pointing the telescope at the moon and using the various
adjustments to move the telescope.
To point the telescope at the moon, loosen the R.A. and Dec. clamps (the
thumbscrews located nearest the Hour Circle and Declination Circle on the
mount), then gently move the optical tube assembly until it points at the
moon. Retighten the R.A. and Dec. clamps before viewing.
While viewing, use the R.A. and Dec. adjustment cables to move the tele-
scope. If a motor drive is attached to the telescope, use the hand conroller
for the motor drive instead of the manual controls to move the telescope. The
adjustment cables feature stops which allow a limited degree of adjustment.
To move past a stop, loosen the clamp for the axis you would like to move
and rotate the optical tube assembly past the stop. Be sure to retighten clamps
before viewing to provide a steady image.
If you notice resistance while moving the optical tube assembly, try adjusting
the counterweight position up or down to properly balance the telescope.
The optical tube assembly should move very easily. Do not force the optical
tube assembly, as you may cause damage to the telescope.
INTERMEDIATEOBSERVATION
Once you are familiar with the basic movements and adjustments of the tele-
scope, expand your exploration to other easy to find objects. Venus is one of
the easiest to find planets as it is one of the brightest objects in the night sky.
Local newspapers and planetariums are excellent resources for finding what
planets should be visible in your area on any given night. Other resources
are mentioned at the end of this manual.
To find a planet, look around the sky to locate the planet with your naked
eye first. Once you have located a planet, point the telescope at the planet.
Center the planet in the finderscope by using the crosshairs. Once the planet
is lined up in the finderscope, view the planet through the telescope using
the lowest power (longest focal length) eyepiece. You may need to make
slight adjustments to your aiming of the telescope and you will need to focus
your eyepiece to properly view the planet.
For a closer look at the planet, replace the low powered eyepiec with a higher
powered one and refocus the telescope.

ADV ANCEDOBSERVATION
STAR CHARTSANDSETT ING CIRCLES
Star charts and setting circles will allow you to find the location of
any known celestial objects viewable by your telescope. By using the
measurements listed on the mount and the coordinates provided in a
star chart, you will be able to find stars, planets, nebulae, and galaxies
for exploration with your telescope. In order to ensure that you can
use the declination and right ascension coordinate system, you will
need to first polar align your telescope for your viewing location.
POLAR ALIGNMENTOF YOU RTELESCO PE
Polar alignment of your telescope uses easy to find stars to help you
find the center of the celestial sphere. Before aligning your telescope,
you must familiarize yourself with some of the major constellations
in the night sky. For viewing in the Northern Hemisphere, knowing
the locations of Polaris (the North Star) and the constellations Ursa
Major (the Big Dipper) and Cassiopeia (the Queen) will allow you
to properly align your telescope. In the Southern Hemisphere, you
will need to use a star chart to find stars near the meridian and the ce-
lestial equator so that you can use the star-drift method to polar align
your telescope. Both Northern and Southern Hemisphere alignment
are described here.
BEFO RE GETT ING STARTED
Before you begin aligning your telescope, look at the mount and
familiarize yourself with the various scales used in aligning your
scope. The topmost scale on the mount is the declination scale,
which shows the declination angle (between 0 and 90 each way) of
what you are viewing. Slightly below the declination scale is the hour
circle, which shows the right ascension (from 0 to 24hours) of what
you are viewing. The bottommost scale, located just above the base
of the mount, is the latitude scale which shows latitude measurements
from 0 to 90 degrees. In order to ensure that your measurements are
correct when aligning your telescope, it is important to make sure
that the base of your mount is level. If the base of the mount is not
level, your measurements will be off and aligning will be much more
difficult.

NORTH ERN HEMISPHERE POLAR ALIGNMENT
1. To align your telescope in the
Northern Hemisphere, first find the
location of Polaris in the night sky.
You can easily find polaris by using
the Big Dipper to “point” at Polaris.
The two stars which make up the
edge of the dipper in the Big Dip-
per will roughly “point” at Polaris.
You can also use the star at the end
of the handle of the Big Dipper and
the star on the edge of the shal-
lower end of Cassiopeia to draw a
line through Polaris. The illustration
shows this.
2. Loosen the declination axis by turning the declination release lever. Turn
the optical tube assembly so that the arrow on the declination scale points at
0 . Once the arrow points at 0 , the optical tube assembly will be pointed 90
from the polar axis and you will be able to use the polar alignment scope.
3. Remove the lenscaps on the polar alignment scope. The objective of the
polar alignment scope should be directly above the north leg of the tripod
(labelled with an N). Turn the telescope, tripod and all, so that the front of
the mount faces north. You can use a compass to find magnetic north and
then line up with Polaris (celestial north) or line up the front of the tele-
scope in line with Polaris by imagining a straight line running from Polaris
down to the horizon.
4. Loosen the latitude adjustment screws. As you loosen the screws, you will
notice the number on the latitude scale change. Adjust the latitude scale until
Polaris is in the center of the polar alignment scope. Check that Polaris is
in the center of the telescope’s field of view by swinging the telescope tube
to 90 on the Dec. axis and looking through the focused eyepiece of the
telescope. The number on the latitude scale should match the latitude of your
viewing location. If there is a difference between the latitude of your viewing
location and the number shown on the latitude scale, check to make sure that

SOUTHERN HEMISPHERE & STAR DRIFT POLAR ALIGNMENT
Polar alignment in the Southern Hemisphere is more difficult that in the
Northern Hemisphere because there is no corresponding pole star to use
for alignment in the Southern Hemisphere. Polar aligning in the Southern
Hemishpere is a two part process because of this. A rough alignment must
first be made based on your viewing location. Then, a star drift alignment
should be made to fine tune your alignment. Star drift alignment is also more
accurate than the other methods described here and will be necessary for
long-exposure astrophotography.
Begin by roughly aligning your telescope to the pole by using the mount’s
latitude scale. Set the declination scale to 0 to align the optical tube asssem-
bly with the mount’s polar axis. Check the latitude of your viewing location
and set the latitude scale to the same number. For example, if you were view-
ing from Sydney, Australia, you would point your telescope due south and
set your latitude adjustment to 34, since Sydney lies at 34S latitude. this will
point you roughly at the southern celestial pole.
1. Having already roughly aligned your telescope, loosen the declination
clamp and swivel telescope until scale reads 90 , then retighten clamp.
Loosen the right ascension clamp and rotate telescope so that it points 6
hours away from the celestial pole and retighten clamp. The R.A. and Dec.
adjustment cables may need to be temporarily removed in order to swivel
the telescope freely. The telescope should now be pointing roughly where
the meridian and celestial equator intersect.
ROUGH ALIGNMENT
STAR DRIFT ALIGNMENT WITH AMOTOR DRIVE
Star Drift alignment is more precise than polar star alignment, but may also
prove to be more difficult to those not used to aligning a telescope. Once you
polar align using the star drift method a few times, it becomes easier, but the
first few times may take a considerable amount of time. For general viewing
uses, the rough alignment described above may prove to be sufficient. The
alignment procedure described below can be used to acheive more accurate
alignment when needed. The alignment is described using a standard eye-
piece without an erecting prism or image diagonal.

2. Find a bright star in the viewfinder of your telescope and use the R.A. and
Dec. adjustment cables to center it in the crosshairs. Work up to your most
powerful eyepiece, centering the star in the viewfinder each time you replace
the eyepiece.
3. Engage the clock drive by tightening the thumbscrew which connects it to
the R.A. axis of the mount. Turn on the clock drive, ensuring that it is set to
the correct hemisphere setting. Let the clock drive run for about 5 minutes.
4. Look into the eyepiece after the clock drive has run for about 5 minutes
to see which direction the star has drifted. If the star has drifted to the south
(north in the Northern Hemisphere) in the eyepiece, the mount is pointed
too far to the west. If the star has drifted to the north (south in the North-
ern Hemisphere), the mount is pointing too far to the east. To correct this,
adjust the rotational stabilization screws and center the star in the eyepiece.
Any drifting east or west in the eyepiece is a result of your clock drive speed
setting and can be corrected by adjusting the clock drive speed.
5. Unengage the clock drive. Loosen the right ascension clamp and rotate
the telescope back 6 hours (opposite the direction you rotated it in step 1).
Find a bright star in the viewfinder and center the star in the viewfinder.
Center this star in the highest power eyepiece as you did with the previous
star. Reengage the clock drive and turn it on, letting it run for another five
minutes.
6. Check to see which way this new star has drifted. If the star has drifted to
the north (south in the Northern Hemisphere) in the eyepiece, the mount
latitude setting is too low. If the star drifts to the south (north in the Northern
Hemisphere) in the eyepiece, the mount latitude setting is too high. Adjust
the latitude setting until the star is centered in the field of view. Again, any
drifting east or west in the eyepiece is a result of your clock drive speed set-
ting and can be corrected by adjusting the clock drive speed.
7. Repeat this process as needed until you are satisfied with the alignment
of the telescope. The more closely polar aligned your telescope is, the more
accurate it will track stars.

POLAR ALIGNMENTUSING TH EFINDERSCO PE
Another method of alignment will work better for aligning your telescope
without the use of a motor drive. The finderscope alignment uses your
finderscope to align your mount to the celestial pole. As you become more
familiar with telescope alignment, you may discover that you prefer one
method over another. The important part of alignment is matching the polar
axis of the mount with the celestial pole and whichever method allows you
to achieve the most accurate alignment is the best one to use.
1. Having already roughly aligned your telescope, loosen the declination
clamp and swivel telescope until Dec. scale reads 90 , then retighten clamp.
Loosen the right ascension clamp and rotate telescope so that the finder-
scope is on the side of the telescope. Look through the finderscope and
center polaris in the finderscope by fine tuning the latitude adjustment and
mount angle by using the latitude adjustment screws and rotational stabiliza-
tion screws.
2. While looking through the finderscope, slowly rotate the telescope 180
around the polar axis (12 hours in Right Ascension) until the finder is on
the opposite side of the telescope. If the optical axis of the finder is parallel
to the polar axis of the mount, then Polaris will not have moved in relation
to the finderscope’s crosshairs. If, on the other hand, Polaris has moved off
of the crosshairs, then the finderscope will need to be aligned with the polar
axis of the mount. If this is the case, you will notice that Polaris will move in
a semi-circle around the point where the polar axis is pointing. Take notice
how far and in what direction Polaris has moved.
3. Using the screws on the finder bracket, make adjustments to the finder-
scope and move the cross hairs halfway towards Polaris’ current position.
Once this is done, adjust the mount itself as in the last step so that Polaris
is once again centered in the cross hairs. Wile looking through the finder-
scope, rotate the telescope back 180 along the R.A. axis to check the find-
erscope alignment.
4. With each successive adjustment the distance that Polaris moves away
from center will decrease. Repeat steps 2 and 3 until Polaris remains cen-
tered on the crosshairs. Once no movement of Polaris in relation to the
crosshairs can be detected, the finderscope is aligned with the polar axis of
the mount.

1. While looking through the finderscope (with Polaris still centered in the
cross hairs) adjust the mount with the latitude and rotational adjustment
screws until Polaris moves toward Alkaid. How far to move Polaris will de-
pend on the field of view of the finderscope. If using a finderscope with a
6 field of view, Polaris should be offset approximately 1/3 of the way from
center to edge in the finder’s view (i.e. half of the field of view, from center
to edge, equals 3 and 1/3 of that equals 1 ). This calculation can be ap-
proximated for any finderscope with a known field of view.
The finderscope is now properly aligned with the polar axis of your mount
and the mount is aligned to Polaris. The actual North celestial pole lies
about 3/4away from Polaris toward Alkaid, the last star in the Big Dipper.
To acheive accurate polar alignment, the polar axis of the telescope must
now be lined up with the north celestial pole.
2. Loosen the R.A. and Dec. axis clamps and aim the telescope at a star near
the celestial equator with known right ascension. Be careful not to move
the mount base or tripod while moving the optical tube. Retighten the axis
clamps.
3. Loosen the R.A. scale tumbscrew and turn the R.A. scale so that the
scale reading matches the right ascension of the star you are centered on.
Retighten the R.A. scale thumbscrew.
4. Using the R.A. and Dec. axis adjustments, turn the telescope so that the
R.A. scale reads 2h30m and the Dec. scale reads 89 1/4. Polaris should
now be centered in the finderscope’s crosshairs. If Polaris is not centered in
the crosshairs, adjust the mount using the latitude and rotational adjustment
screws until Polaris is centered in the crosshairs of the finderscope. Your
mount is now polar aligned.

FINDING CELESTIAL OBJ ECT S
Once your telescope is polar aligned, you must set the hour circle in order to
use the measurements listed on the mount to find celestial objects. Once the
hour circle is properly set, you will be able to use the coordinates listed on
star charts to find objects for viewing in the night sky. Setting the hour circle
will require that you recognize and be able to find a star other than the ones
used for alignment of the telescope.
To set the hour circle, use a star which you are able to easily identify and
have the coordinates for. In the Northern Hemisphere, Dubhe is a recogniz-
able star which can be used for this. Dubhe is the pointer star in the Big Dip-
per closest to Polaris and lies at 58 42’ Dec., 11h23m R.A.. In the Southern
Hemisphere, Acrux is an easy to find star for setting the hour circle. Acrux is
the closest star to the southern celestial pole in the Southern Cross and lies
at -63 15’ Dec., 12h33m R.A..
SETT ING TH EHOU RCIRCLE
1. Loosen the declination clamp and rotate the telescope to the nearest de-
gree of declination to the star you will be viewing (58 for Dubhe, -63 for
Acrux). Retighten the clamp to lock the declination in place.
2. Loosen the right ascension clamp and rotate the telescope on the R.A.
axis until the star you are using to set the hour circle is near the center of the
finderscope. Retighten the clamp to lock in the R.A. axis.
3. Center the star in the eyepiece using the R.A. and Dec. adjustment cables.
Once it is centered, turn the hour circle until the arrow points at the ap-
propriate measurement for the star you are looking at (11h23m for Dubhe,
12h33m for Acrux). This sets the hour circle to the appropriate setting for
your viewing location and time.
USING SETT ING CIRCLES
With the telescope polar aligned and the hour circle set, you can find celes-
tial objects using star charts available in books or on the web. A star chart
will normally consist of a map and an ephemeris. The ephemeris will tell
you the celestial coordinates of an object. By using the hour circle and the
declination circle, you can point your telescope at the objects you see on
the star chart quickly and easily. You will probably need to fine tune your
aiming with the adjustment cables when you view a new star, but the use of
celestial coordinates will make finding the objects you would like to look at
considerably easier.