Kepler Manual[1]

8/4/2019 Kepler Manual[1]

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KEPLER 152


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WARNINGS

Do not use telescope or finderscope to look at the sun withoutan appropriate solar filter.

Make sure no screws are loose before using telescope.

Do not drop, shake, or throw your telescope as doing so maydamage the telescope or people around you.

Objects in telescope may be farther away than they appear.Eyepieces intended for external use only.Dont worry, be happy...

Zhumell telescopes are precision astronomical instruments de-signed to be easy to use and versatile in their application. As withany telescope, Zhumell telescopes require some technical knowl-edge of stellar movement and optical properties. We have tried toprovide the basics of telescope use and astronomical viewing inthis manual. If, after reading through this manual, you still havequestions regarding the setup and use of your telescope, pleasefeel 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 websiteat www.zhumell.com. Please let us know about your experienceswith your Zhumell telescope. We would like to hear your feed-back and see your astrophotographs. Enjoy your Zhumell.

INTRODUCTION


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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 Assembly8x50 FinderscopeEQ5 Equitorial MountAdjustable Speed Clock Drive with Hand Controller

R.A. and Dec. Adjustment KnobsCounterweight (2)Aluminum TripodAccessory Tray6.5mm and 20mm Plossl Eyepieces1.25 Image Diagonal


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1. Tripod2. Mount Assembly3. Optical Tube Assembly

4. Eyepiece5. Finderscope6. Optical Tube Mounting Belt7. Focuser8. Image Diagonal9. Dec. Adjustment Knob10. Dec. Axis Release11. Declination Scale

12. Hour Circle (R.A. Scale)13. Polar Alignment Scope14. Latitude Scale15. Latitude Adjustment16. Counterweight17. Counterweight Shaft

T ELESCO PE LEGEND

2

1

3

4

5

6

7

8


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C AREOF YOU RT ELESCO PE

A telescope is carefully aligned during construction and great care shouldbe 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 solutionand soft, lint-free cloth. Do not rub elements when cleaning. Blot opticalcomponents gently and allow telescope to air dry. Store telescope in boxwhen not in use. Do not use alcohol or solvents to clean any parts of thetelescope. Do not remove optical elements from telescope as doing so mayaffect the alignment of optical components when reassembled. If telescopeneeds realignment, contact Zhumell or another professional.

13

9

10

11

17

16

12

15

6

14


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T ELESCO PE ASSEMB LY

1. Extend tripod legs to comfortable workingheight and tighten wingnuts to ensure stabil-ity. Separate tripod legs and ensure that the

legs are extended to equal heights. The top ofthe tripod should be level to ensure stabilitywhen mounting telescope.

2. Remove accessory tray mounting screw atthe 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 andtighten 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 locatethe mount rotational stabilization thumbscrews

below the front latitude adjustment screw.

4. Remove the mount base screw. Loosen themount rotational stabilization thumbscrewsenough to allow the alignment prong to beinserted between the bases of the screws. Setthe mount on the top of the tripod so that thetripod alignment prong is lined up betweenthe mount rotational stabilization screws.

Tighten rotational stabilization screws so thatthe fron mount extrusion is centered over thenorth tripod leg. Isert the mount base screwthrough the hole in the tripod platform andhand tighten.


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6. Holding the counterweight shaft, turn theDec. axis cap attached to the shaft clockwise(looking at the large end of the cap) until itstops. Insert the shaft into the counter-weightshaft socket and screw the shaft into the socketunti secure. To eliminate the gap between theDec. axis cap and the Dec. axis of the mount,

turn cap (without turning the counterweightshaft) until it is snug with the end of the Dec.axis.

7. Remove screw located at the end of thecounterweight shaft. Loosen the thumbscrewson the counterweights until shaft opening inthe counterwiegt is completely unobstructed.With the thumbscrew pointing down, slidethe counterweight up the counterweight shaftand tighten counterweight thumbscrew untilsnug. Repeat for each counterweight. Replacethe end screw of the counterweight shaft and

tighten until snug.

5. Loosen R.A. and Dec. axes by turning axisrelease levers 180. Position mount so thatDec. axis is at 0 and R.A. Axis is at 0, thenre-tighten the axis release levers. The mountshould now vertically level. With the mount in

this vertical position, find the counter-weightshaft socket located at the end of the Dec. axisabove the north leg of the tripod.


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8. Loosen the two thumbscrews located at thetop of the mount to allow the optical tubemounting rings to be inserted in the groove.Place the optical tube mounting rings into thegroove and tighten the large thumbcrew until

the end of the screw is snug against the opticaltube mounting ring base. Tighten the smallscrew against the optical tube mounting ringbase to add stability to the moounting rings.

9. Open optical tube mounting rings byloosening thumbscrews on side of mount-ing rings. Lift the optical tube assembly bythe attached handle near the focuser andset it into the optical tube mounting rings,guiding it with your other hand. Close theoptical tube mounting rings and retighten the

thumbscrews on the mounting rings to secureoptical tube assembly.

10. Remove nuts from finderscope mount-ing bolts near the focuser on the optical tubeassembly. Slide finderscope mount over thebolts and replace nuts, turning them until theyare snug against the finderscope mount.

11. Loosen finderscope mounting screwsuntil finderscope can be easily slid into themount. Slide finderscope into the mount andretighten mounting screws so that finderscopeis approximately aligned with the telescope.


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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 intothe 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 imagediagonal, loosen eyepiece receptacle thumb-screw at end of focuser. Remove dustcover

from eyepiece receptacle. Insert chromedend of eyepiece into the eyepiece receptacle.Re-tighten eyepiece receptacle thumbscrew tosecure 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 eyepieceand retighten thumbscrews to secure.

ASSEMB LY NOT ES

In order to avoid visible vibration when viewing at high magnification,adjust the counterweight position on the counterweight shaft to offset theweight of the optical tube assembly and balance the telescope.

When placing the optical tube assembly into the mounting rings, center therings along the length of the optical tube assembly. Centering the rings alongthe 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.


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CLOCK DRIVE CONTROLS

Direction and SpeedControls

Hemisphere and PowerSetting

Battery Pack Connection

Motor Connection Cord

CONNECTINGTHE HAND CONTROLLER

To use the clock drive, connect the havd controller by plugging the MotorConnection Cord into the receptacle at the base of the plastic housing on theR.A. drive of the mount. Place 4 D-cell batteries into the battery pack andplug the power cord from the battery pack into the Battery Pack Connectionreceptacle in on the hand controller. To activate the hand controller, simplyswitch the hemisphere setting to the appropriate setting and press the desiredspeed and direction button.


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USINGTHE 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 periodsof 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 anddo not see the telescope moving. Stars appear to move very slowly and thetelescope may not apear to move over a short period of time. To see if yourclock drive is working, aim the telescope at a stationary terrestrial object andengage the clock drive. Let the clock drive run for 10 to 15 minutes. If theobject you had originally aimed the telescope at appears to have moved whenlooking 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 controlthe 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 switchshould be set to the lower position. The speed setting should be adjustedwhile viewing to help keep stars centered in the field of view. You may haveto increase or decrease your speed setting if stars appear to drift in your fieldof 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 celestialpole (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 ADJUSTMENTWITH CLOCK DRIVE

The clock drive included with your telescope should only be used to followstars. When you would like to point your telescope at a different celestialobject, you must disengage the clock drive. By loosening the thumbscrew

on the clock drive R.A. axis, you will disengage the clock drive, protectingthe clock drive and making manual adjustment easier. Manually adjusting theR.A. axis with the clock drive engaged may cause the gearing in the clockdrive to strip, compromising the operation of the clock drive. When youwould like to reengage the clock drive, simply tighten the thumbscrew anduse the clock drive hand controller to begin tracking stars.


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F IND ERSCO PE ALIGNM ENT

1. Insert the lowest power eyepiece into the eyepiece adapter. Focus eyepieceto view an easily recognizable distant object (car license plate, sign, table,etc.).

2. Look through finderscope being careful not to move the telescope in anyway. Adjust finderscope focus by turning the eyepiece of the finderscopeback and forth until image is in focus. Check to see if the object viewedthrough the eyepiece lines up at the center of the finderscope crosshairs. Ifnot, 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 takesome time, but will make finding astronomical objects much easier whenusing your telescope.

SOM ENOT ESO NV IEWING

N ever 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 thelenscap. 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 desiredmagnificaiton 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.


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B EGINNINGO B SERVAT IO N

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 thetelescope 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 (thethumbscrews located nearest the Hour Circle and Declination Circle on themount), then gently move the optical tube assembly until it points at themoon. 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. Theadjustment 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 moveand rotate the optical tube assembly past the stop. Be sure to retighten clampsbefore viewing to provide a steady image.If you notice resistance while moving the optical tube assembly, try adjustingthe counterweight position up or down to properly balance the telescope.

The optical tube assembly should move very easily. Do not force the opticaltube assembly, as you may cause damage to the telescope.

INTERM ED IATEO B SERVAT IO N

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 ofthe 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 whatplanets should be visible in your area on any given night. Other resourcesare mentioned at the end of this manual.

To find a planet, look around the sky to locate the planet with your nakedeye 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 planetis lined up in the finderscope, view the planet through the telescope usingthe lowest power (longest focal length) eyepiece. You may need to makeslight adjustments to your aiming of the telescope and you will need to focusyour 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.


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ADV ANC ED O B SERVAT IO N

STARC H ARTSAND SETT INGC IRC LES

Star charts and setting circles will allow you to find the location ofany known celestial objects viewable by your telescope. By using the

measurements listed on the mount and the coordinates provided in astar chart, you will be able to find stars, planets, nebulae, and galaxiesfor exploration with your telescope. In order to ensure that you canuse the declination and right ascension coordinate system, you willneed to first polar align your telescope for your viewing location.

PO LAR ALIGNM ENTOF YOU RT ELESCO PE

Polar alignment of your telescope uses easy to find stars to help youfind 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 theN

orthern Hemisphere, knowingthe locations of Polaris (the North Star) and the constellations UrsaMajor (the Big Dipper) and Cassiopeia (the Queen) will allow youto properly align your telescope. In the Southern Hemisphere, youwill 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 alignyour telescope. Both Northern and Southern Hemisphere alignment

are described here.

B EFO RE GETT ING STARTED

Before you begin aligning your telescope, look at the mount andfamiliarize yourself with the various scales used in aligning yourscope. The topmost scale on the mount is the declination scale,which shows the declination angle (between 0 and 90 each way) ofwhat you are viewing. Slightly below the declination scale is the hourcircle, which shows the right ascension (from 0 to 24 hours) of whatyou are viewing. The bottommost scale, located just above the baseof the mount, is the latitude scale which shows latitude measurementsfrom 0 to 90 degrees. In order to ensure that your measurements arecorrect when aligning your telescope, it is important to make surethat the base of your mount is level. If the base of the mount is notlevel, your measurements will be off and aligning will be much moredifficult.


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NO RTH ERNH EM ISPH ERE PO LAR ALIGNM ENT

1. To align your telescope in theN

orthern Hemisphere, first find thelocation of Polaris in the night sky.You can easily find polaris by usingthe Big Dipper to point at Polaris.

The two stars which make up theedge of the dipper in the Big Dip-per will roughly point at Polaris.

You can also use the star at the endof the handle of the Big Dipper andthe star on the edge of the shal-lower end of Cassiopeia to draw aline through Polaris. The illustrationshows this.

2. Loosen the declination axis by turning the declination release lever. Turnthe optical tube assembly so that the arrow on the declination scale points at0 . Once the arrow points at 0 , the optical tube assembly will be pointed 90from 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 thepolar 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 ofthe mount faces north. You can use a compass to find magnetic north andthen 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 Polarisdown 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 untilPolaris is in the center of the polar alignment scope. Check that Polaris isin the center of the telescopes field of view by swinging the telescope tubeto 90 on the Dec. axis and looking through the focused eyepiece of thetelescope. The number on the latitude scale should match the latitude of yourviewing location. If there is a difference between the latitude of your viewinglocation and the number shown on the latitude scale, check to make sure that


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SOUTHERN HEMISPHERE & STAR DRIFT POLAR ALIGNMENT

Polar alignment in the Southern Hemisphere is more difficult that in theNorthern Hemisphere because there is no corresponding pole star to usefor alignment in the Southern Hemisphere. Polar aligning in the SouthernHemishpere is a two part process because of this. A rough alignment must

first be made based on your viewing location. Then, a star drift alignmentshould be made to fine tune your alignment. Star drift alignment is also moreaccurate than the other methods described here and will be necessary forlong-exposure astrophotography.

Begin by roughly aligning your telescope to the pole by using the mountslatitude scale. Set the declination scale to 0 to align the optical tube asssem-bly with the mounts polar axis. Check the latitude of your viewing locationand 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 andset your latitude adjustment to 34 , since Sydney lies at 34 S latitude. this will

point you roughly at the southern celestial pole.

1. Having already roughly aligned your telescope, loosen the declinationclamp and swivel telescope until scale reads 90 , then retighten clamp.

Loosen the right ascension clamp and rotate telescope so that it points 6hours away from the celestial pole and retighten clamp. The R.A. and Dec.adjustment cables may need to be temporarily removed in order to swivelthe telescope freely. The telescope should now be pointing roughly wherethe meridian and celestial equator intersect.

ROUGH ALIGNMENT

STAR DRIFT ALIGNMENTWITHA MOTOR DRIVE

Star Drift alignment is more precise than polar star alignment, but may alsoprove to be more difficult to those not used to aligning a telescope. Once youpolar align using the star drift method a few times, it becomes easier, but thefirst few times may take a considerable amount of time. For general viewing

uses, the rough alignment described above may prove to be sufficient. Thealignment procedure described below can be used to acheive more accuratealignment when needed. The alignment is described using a standard eye-piece without an erecting prism or image diagonal.


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2. Find a bright star in the viewfinder of your telescope and use the R.A. andDec. adjustment cables to center it in the crosshairs. Work up to your mostpowerful eyepiece, centering the star in the viewfinder each time you replacethe eyepiece.

3. Engage the clock drive by tightening the thumbscrew which connects it tothe R.A. axis of the mount. Turn on the clock drive, ensuring that it is set tothe 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 minutesto 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 pointedtoo 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 speedsetting and can be corrected by adjusting the clock drive speed.

5. Unengage the clock drive. Loosen the right ascension clamp and rotatethe 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 previousstar. Reengage the clock drive and turn it on, letting it run for another fiveminutes.

6. Check to see which way this new star has drifted. If the star has drifted tothe north (south in the Northern Hemisphere) in the eyepiece, the mountlatitude setting is too low. If the star drifts to the south (north in the NorthernHemisphere) in the eyepiece, the mount latitude setting is too high. Adjustthe latitude setting until the star is centered in the field of view. Again, anydrifting 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 alignmentof the telescope. The more closely polar aligned your telescope is, the moreaccurate it will track stars.


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PO LAR ALIGNM ENT U SINGTH EF IND ERSCO PE

Another method of alignment will work better for aligning your telescopewithout the use of a motor drive. The finderscope alignment uses yourfinderscope to align your mount to the celestial pole. As you become morefamiliar with telescope alignment, you may discover that you prefer one

method over another. The important part of alignment is matching the polaraxis of the mount with the celestial pole and whichever method allows youto achieve the most accurate alignment is the best one to use.

1. Having already roughly aligned your telescope, loosen the declinationclamp 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 andcenter polaris in the finderscope by fine tuning the latitude adjustment andmount angle by using the latitude adjustment screws and rotational stabiliza-tion screws.

2. While looking through the finderscope, slowly rotate the telescope 180around 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 parallelto the polar axis of the mount, then Polaris will not have moved in relationto the finderscopes crosshairs. If, on the other hand, Polaris has moved offof the crosshairs, then the finderscope will need to be aligned with the polaraxis of the mount. If this is the case, you will notice that Polaris will move ina semi-circle around the point where the polar axis is pointing. Take noticehow 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 Polarisis 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 awayfrom center will decrease. Repeat steps 2 and 3 until Polaris remains cen-tered on the crosshairs. Once no movement of Polaris in relation to thecrosshairs can be detected, the finderscope is aligned with the polar axis ofthe mount.


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1. While looking through the finderscope (with Polaris still centered in thecross hairs) adjust the mount with the latitude and rotational adjustmentscrews 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 a6 field of view, Polaris should be offset approximately 1/3 of the way fromcenter to edge in the finders 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 mountand the mount is aligned to Polaris. The actual North celestial pole liesabout 3/4 away from Polaris toward Alkaid, the last star in the Big Dipper.

To acheive accurate polar alignment, the polar axis of the telescope mustnow be lined up with the north celestial pole.

2. Loosen the R.A. and Dec. axis clamps and aim the telescope at a star nearthe celestial equator with known right ascension. Be careful not to movethe mount base or tripod while moving the optical tube. Retighten the axisclamps.

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 theR.A. scale reads 2h30m and the Dec. scale reads 89 1/4 . Polaris shouldnow be centered in the finderscopes crosshairs. If Polaris is not centered inthe crosshairs, adjust the mount using the latitude and rotational adjustment

screws until Polaris is centered in the crosshairs of the finderscope. Yourmount is now polar aligned.


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F IND INGC ELEST IALO BJ ECT S

Once your telescope is polar aligned, you must set the hour circle in order touse the measurements listed on the mount to find celestial objects. Once thehour circle is properly set, you will be able to use the coordinates listed onstar charts to find objects for viewing in the night sky. Setting the hour circlewill require that you recognize and be able to find a star other than the onesused for alignment of the telescope.

To set the hour circle, use a star which you are able to easily identify andhave 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 SouthernHemisphere, Acrux is an easy to find star for setting the hour circle. Acrux isthe closest star to the southern celestial pole in the Southern Cross and liesat -63 15 Dec., 12h33m R.A..

SETT INGTH EH OU RC IRC LE

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 thefinderscope. 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 foryour viewing location and time.

U SING SETT INGC IRC LES

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 chartwill normally consist of a map and an ephemeris. The ephemeris will tellyou the celestial coordinates of an object. By using the hour circle and thedeclination circle, you can point your telescope at the objects you see onthe star chart quickly and easily. You will probably need to fine tune youraiming with the adjustment cables when you view a new star, but the use ofcelestial coordinates will make finding the objects you would like to look at

considerably easier.


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ASTRO NOMY F OMU LAE

MagnificationTo determine the magnification of a telescope and eyepiece combina-tion, divide the telescope focal length be the eyepiece focal length.

Magnification (x) = Telescope Focal Length (mm)/Eyepiece Focal Length (mm)

Ex: 20mm Eyepiece with a 70x900mm telescope.Magnification = 900mm/20mmMagnification = 45x

Focal Ratio

To determine the focal ratio of a telescope, divide the focal length ofthe telescope by the aperture.

Focal Ratio (F/x)= Telescope Focal Length (mm)/Aperture (mm)

Ex: Focal Ratio of a 70x900mm telescope.Focal Ratio (F/x)= 900mm/70mmFocal Ratio (F/x)= F/12.8

Limiting MagnitudeTo determine the limiting magnitude of a telescope, use the aperture inthe following formula for an approximation.

Limiting Magnitude = 7.5 + 5LOG(Aperture in cm)

Ex: Limiting Magnitude of a 114x1000mm telescope.Limiting Magnitude = 7.5 + 5LOG(11.4cm)Limiting Magnitude = 7.5 + (5 x 1.057)Limiting Magnitude = 12.785

Resolving Power

To determine the resolving power of a telescope under ideal conditions,divide the aperture into 4.56.

Resolving Power = 4.56/Aperture (in.)

Ex: Resolving Power of a 114x1000mm telescope.Aperture (in.) = 114mm/25.4 = 4.49Resolving Power = 4.56/4.49in.

Resolving Power = 1.02


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ASTRO NOMY T ERM INO LO GY

DECLINATION (DEC.) - The astronomical equivalent of latitude. Declination describes theangle of a celestial object above or below the celestial equator. The sky over the northernhemisphere has a positive declination. The sky over the Southern hemisphere has a negativedeclination. For example, Polaris (the North Star) which lies nearly directly over the NorthPole, has a declination value of 90 .

RIGHT ASCEN SION (R.A.) - The astronomical equivalent of longitude. Right Ascension mea-sures the degree of distance of a star to the east of where the ecliptic crosses the celestialequator. R.A. is measured in hours, minutes, and seconds as opposed to degrees. As oposedto the term meridian which is used in referring to lines of longitude, right ascension isreferred to as hour circles. There are 24 hour circles of right ascension which run from thenorth to south celestial poles.

CELESTIAL EQUATOR - The celestial equator is the line of declination which lies directly abovethe Earths equator. The celestial equator lies halfway between the north and south celestialpoles and serves as the 0 point in measuring declination.

ECLIPTIC - The ecliptic is the apparent path of the sun through the sky over the course of theyear. Since we view the sun from different angles throughout the year, it appears to movein relation to other stars. The vernal (spring) and autumnal (fall) equinoxes lie at the points

where the ecliptic intersects the celestial equator. The vernal equinox is where right ascensionis at 0 h (hours). The autumnal equinox can be found at 12 h R.A..

ZEN ITH - The zenith is the point in the celestial sphere directly above your head. The zenithvaries depending upon your location. In general, the declination point of your zenith isequal to the latitude at which you are standing on Earth.

EPHEMERIS - The ephemeris of a planet or the sun or the moon is a table giving the coordi-nates of the object at regular intervals of time. The coordinates will be listed using declina-

tion and right ascension. Other information such as distance and magnitude may be listedin ephemerides (plural of ephemeris).

ALTITUDE - The altitude of a celestial object is the angular distance of that object above thehorizon. The maximum possible altitude is the altitude of an object at the zenith, 90 . Thealtitude of an object on the horizon is 0 . Altitude is measured from your point of observa-tion and does not directly correlate to points on the celestial sphere.

AZIMUTH - Azimuth is the angular distance around the horizon measured eastward in de-grees from the North Horizon Point. Thus the North Horizon Point lies at an azimuth of0 , while the East Horizon Point lies at 90 , and the South Horizon Point at 180 . Azimuthis measured from the point of observation and does not directly correspond to points onthe celestial sphere.

ANGULAR DISTANCE - Angular distance is the size of the angle through which a telescopetube aiming at one object must be turned in order to aim at the another object. If you mustrotate the telescope from the zenith to the horizon, the angular distance between the two

points would be 90 .


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T ELESCO PET ERM INO LO GY

OBJECTIVE - The objective is the front lens of a telescope. The measurement listed for objec-tive lenses is the diameter of the lens. A larger objective allows more light to enter a telescopeand provides a brighter image. The objective diameter is also sometimes referred to as theaperature of a telescope.

FOCAL LENGTH - The focal length of a telescope is the distance from the point where lightenters a telescope (the objective) to the point where the image is in focus. In telescopeswith the same size objective, a longer focal length will provide higher magnification and asmaller field of view.

MAGNIFICATION - The magnification of a telescope is determined by the relationship betweenthe focal length of the telescope and the focal length of the eyepiece used. The greater the

difference in focal lengths, the greater the magnification. A telescope has a maximum use-ful magnification of about 60 times the diameter of the objective in inches. Magnificationbeyond the maximum useful magnification will provide dim, low-contrast images.

FOCAL RATIO - The focal ratio of a telescope describes the ratio between the focal lengthand objective size of a telescope. Visually, the smaller the focal ratio (also called f-stop) of atelescope, the wider the field of view. Photographically, the lower the f-stop, the shorter theexposure time needed to capture an object on film.

LIMITING MAGNITUDE - The limiting magnitude of a telescope describes the faintest objectyou can see with a telescope. The magnitude of a star describes its brightness. The larger themagnitude of an object, the fainter it appears to be. The brightest stars have a magnitudeof 0 or less.

RESOLVING POWER - The resolving power, or Dawes Limit, of a telescope is the abilityto view closely spaced objects through a telescope. The resolving power of a telescope ismeasured in seconds of arc. The smaller the resolving power, the better you will be able toseparate binary stars when viewing through your telescope.

ABERRATION - Aberrations are degradations in image which may occur due to optical systemdesign or improper alignment of optical system components. The most common typesof aberration are chromatic aberration, spherical abberation, coma, astigmatism, and fieldcurvature.

COLLIMATION - Collimation is the alignment of optical components within an optical system.Improper collimation will distort an image and may result in abberations present in the im-age. Most reflector telescopes have collimation adjustments which can be made in order to

reduce aberrations and image distortion.


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C OMMO NT ELESCO PED ESIGNS

Refractor Light Path Diagram

AdvantagesEasy to use and reliable designLittle or no maintenance requiredHigh contrast imagesNo secondary or diagonal obstruc-tionSealed optical tube reduces air cur-rents which can degrade imagesObjective lens permanently mountedand aligned

Disadvantages:Most expensive per inch of apertureGenerally longer and heavier thanequivalent reflectors or catadioptricsLess suited for deep sky and faintobject viewing due to size and costlimitations

Reflector Light Path DiagramAdvantages:Least expensive per inch of apertureReasonably compact and portableLow in optical aberrationsExcellent for faint deep sky objects

Disadvantages:Not suitable for terrestrial viewingRequire frequent collimation of opti-cal componentsSome light loss due to secondary ob-struction from secondary mirror

Catadioptric Telescopes

Catadioptric Light Path Diagram

Advantages:Excellent deep sky viewing and imag-ing capabilitiesWorks for terrestrial viewingVery versatile, all-purpose designLittle maintenance requiredSealed optical tube reduces air cur-

rents which can degrade images

Disadvantages:Some light loss due to secondary ob-struction from secondary mirrorCollimation of optics, if required, canbe difficultGenerally more expensive than reflec-tor telescopes


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Refractor TelescopesRefractor telescopes use a series of concave and convex lenses to bend light coming inthe objective lens to a focus at the eyepiece. The light path travels straight through theoptical tube without any mirrors needed to redirect the light toward the eyepiece.

Reflector Telescopes

Reflector telescopes use a series of mirrors to bring light to focus at the eyepiece, whichextrudes from the side of the telescope tube. Light enters the open objective end of thetube and is then bounced off of a parabolic mirror toward the secondary mirror. Thesecondary mirror redirects the light out of the side of the tube toward the eyepiece. Thesecondary mirror blocks a small portion of the light coming in the front of the opticaltube as it is in the light path.

Telescope Image Orientation

Catadioptric Telescopes

Catadioptric telescopes combine lenses and mirrors to bring light to focus at the eye-piece, which extrudes either out the side of the optical tube, or through a hole in thecenter of the primary mirror. Catadioptric telescopes provide a wider field of view thanreflector telescopes and correct focus to be the same across the entire field of view. Cata-dioptric telescopes also lose a small portion of the light they gather due to obstructionby the secondary mirror.

Image OrientationImages viewed through a telescope will appear to be flipped both horizontally andvertically (rotated 180 ). When viewing celestial objects, image orientation is of littleconcern, but if you would like to use your telescope for terrestrial use, you will needto use an erecting prism to correct the image orientation. An image diagonal will alsopartially correct the image by flipping the image vertcally, but the image will still ap-pear backwards. To correct the image in a reflector telescope, you will need a par-focalerecting eyepiece which also increases the magnificaiton of your eyepiece by a factor

of 1.5x.

Telescope Image with Diagonal

Telescope Image with Erecting Prism


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THE ZHUMELL WARRANTY

We have designed Zhumell products to be durable and to offer excellent value.Because we think it is important to stand behind that statement what follows arethe details of our warranty, one of the best warranties in the industry.Your Zhumell has a 3-year warranty. For the warranty to be valid, the Zhumell

must be registered. This can be done quickly and easily at www.zhumell.com orby calling: 800.922.2063.

To obtain warranty service the damaged Zhumell must be returned to Zhumellalong with $25 to cover shipping and handling.When you return your Zhumell to us please send a letter that explains the problem.

This is important. Sometimes the problem is obvious as when we open a box andthe pieces fall out. However, sometimes Zhumell owners are particular (that is whywe love you) and a flaw that you have noticed may be hard to find by our techni-

cian. A letter will speed up the warranty process and save a phone call. (Oh, yes,please include your phone number and an address!)Since we are constantly searching for the best products, we may have improved orchanged our Zhumell products from the time you first obtained yours, therefore itis our option to repair or replace the Zhumells you sent us. (Please note that themaximum limit of liability for losses or damage from any cause shall be the pricepaid for the Zhumell. )

REPAIR CHECKLIST

I.Box your Zhumell securely.II.Include a note explaining the reason the Zhumell needs repair.III.Include your daytime phone number.

IV.Include an address for returning your Zhumell to you.V.Include a check or money order for $25, made out to Zhumell.

We recommend that you send your unit to us by way of UPS or FedEx. This pro-vides a tracking number should your unit become lost or damaged.

Our address is on the back...


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Z HUM ELL ASTRO NOM IC AL PRODUCT S

REFRACTO RT ELESCO PES

60x350 Ion60x600 ZenithAurora 70Kepler 152

REFLECTO RT ELESCO PES

Eclipse 114Tycho 254

ASTRO NOM IC ALB INOCU LARS

20x80 Super Giant25x100 Tachyon

IM AGED IAGO NALS

1.25 to 1.25 90 Diagonal PrismERECT IM AGE PRISM S

0.965 to 0.965 45 Erect Image Prism1.25 to 0.965 45 Erect Image Prism1.25 to 1.25 45 Erect Image Prism

B ARLO W LENSES

1.25 2x Barlow

1.25 3x Barlow

T ELESCO PE EYEPIEC ES

0.965 6.3mm Plssl0.965 7.5mm Plssl0.965 10mm Plssl

0.965 12.5mm Plssl

0.965 17mm Plssl0.965 20mm Plssl0.965 25mm Plssl1.25 6.3mm Plssl1.25 7.5mm Plssl1.25 10mm Plssl

1.25 12.5mm Plssl1.25 17mm Plssl1.25 20mm Plssl1.25 25mm Plssl1.25 32mm Plssl1.25 40mm Plssl

1.25 3.6mm Super Plssl1.25 6.3mm Super Plssl1.25 10mm Super Plssl

1.25 20mm Super Plssl1.25 25mm Super Plssl

PLO SSL

SU PER PLO SSL

Z OOM

1.25 7-21mm Plssl Zoom1.25 8-24mm Plssl Zoom

WWW.ZHUM

ELL.COM

B

UYO

NLINE

Hubble Telescope Image

Photo by jason Baumgarth

KITS

1.25 Small Scope Eyepiece

and Filter Kit1.25 Big Scope Eyepieceand Filter Kit

ACCESSORIES

Laser CollimatorEyepiece Case

PHOTO ADAPTERS

1.25 Universal Camera Adapter

1.25 Tele-camera Adapter


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Please enjoy your Zhumell telescope. If you haveany questions, comments, or stories about expe-riences with your Zhumell telescope, we wouldlike to hear them. We are confident that you willbe pleased with your new Zhumells and hope tohear from you soon.

SPO RT O PT IC S

30 E. SUPERIOR ST.DULUTH, MN 55802USA

(800)922-2063HTTP://WWW.ZHUMELL.COM

IN [email protected]

Documents

Kepler Manual[1]