Meade 12.5 Telescope User Manual
Contents
1. fine annealed Grade A Pyrex glass fine annealed Primary amp Secondary Mirrors Secondary Mirror Support 4 vane steel 4 vane steel 4 vane steel Focal Length 1220mm 1220mm 1140mm Focal Ratio f 8 f 6 f 4 5 Resolving Power arc secs 0 74 0 56 0 45 Limiting Visual Magnitude 13 5 14 0 14 5 Limiting Photographic Magnitude 16 0 16 5 17 0 Image Scale 1 187 inch 1 187 inch 1 26 inch Maximum Practical Visual Power 400X 500X 600X 35mm Angular Film Coverage 1 11 x 1 58 1 11 x 1 58 1 199 x 70 12 7 dia x 45 long spiral wound Sonotube 9 6 dia x 48 long spiral wound Sonotube 7 6 dia x 48 long spiral wound Sonotube Optical Tube Secondary Mirror Minor Axis 1 18 1 83 2 37 Secondary Mirror Obstruction 3 9 3 6 5 6 Dobsonian Mounting Base Diameter 13 75 17 1 22 2 Mount Dimensions approx 12 square x 19 high 16 square x 17 high 21 square x 20 high Materials All models thermally fused Melamine with industrial particle board core Bearings Altitude Nylon Nylon Nylon Azimuth Teflon Teflon Teflon Net Weights Optical Tube 20 Ibs 26 lbs 30 Ibs Mounting 14 Ibs 18 Ibs 32 lbs Shipping Weight approx 38 Ibs 49 lbs 68 lbs Meade Instruments Corporation World s leading manufacturer of astronomical telescopes for the serious amateur C3 6001 Oak Canyon Irvine California 92620 949 451 1450 Fax 949 451 1460 www meade com Ver 0499 Part no2. Spider Vane Adjustments 7 Secondary Mirror Adjustments 7 Primary Mirror Adjustments 4 7 Star Testing the Collimation aaan 8 Tips on Using a Dobsonian Telescope 8 olo RR RR CORR CD 8 Gol aed Arr Ra RON id 9 Observing Guidelines llle 9 Care of Optics and Main Tube 9 Optional Accessories 00 9 Meade Customer Service 7 10 Specifications and Features lusu 11 amp The name Meade and the Meade logo are trademarks registered with the U S Patent Office and in principal countries throughout the world 1999 Meade Instruments Corporation 4 Firmly press the screw cover caps 2 Fig 2 into the heads of the wood screws on the side boards You may have to lightly tap the screw cover caps to properly seat them into the screw heads 5 Install the two handles 1 Fig 2 onto the side boards utilizing the supplied screws Firmly tighten the screws 6 To install the center pivot bearing first insert the nylon center bearing bushing 8 Fig 2 into the center hole of the ground plate 10 Fig 2 from the top side You may have to lightly tap the bushing to fully seat it into the hole 7 Place the four six on the 12 5 model nylon washers 9 Fig 2 onto the nylon center bearing bushing Then from the bottom insert the 2 1 4 x 5 16 hex pivot bolt 12 Fig 2 with a flat washer 13 Fig 2 up thr
3. 14 0218 00
4. factors the focal length of the eyepiece employed and the focal length of the telescope The Meade Starfinder Dobsonian telescope is supplied with one eyepiece as standard equipment The focal length of the eyepiece 25mm is printed on its side Telescope focal length is roughly speaking the distance that light travels inside the telescope before reaching a focus The focal length of the Dobsonian 6 f 8 1220mm The focal length of the Dobsonian 8 f 6 1220mm The focal length of the Dobsonian 10 f 4 5 1140mm The focal length of the Dobsonian 12 5 f 4 8 1525mm On a given telescope such as the Starfinder Dobsonian different eyepiece focal lengths are used to achieve different magnifications from low to high To calculate the magnification obtained with a given eyepiece use this formula Power Telescope Focal Length Eyepiece Focal Length Example Using the 25mm eyepiece supplied with the 8 f 6 the power Is Power 1220mm 49x 25mm The type of eyepiece whether Modified Achromatic Plossl or Super Pl ssl has effect on magnification but does have a bearing on such optical characteristics as field of view flatness of field and color correction Maximum practical magnification is about 50X per inch of aperture Generally however lower powers will produce higher image resolution When unsteady air conditions prevail as witnessed by rapid twinkling of the stars extremely high powers resul
5. mountaintops objects previously viewed only in the city take on added detail or are seen in wider extension or even become visible at all for the first time The amateur astronomer is faced typically with two broadly defined problems when viewing astronomical objects through the Earth s atmosphere first is the clarity or transparency of the air and secondly the steadiness of the air This latter characteristic is often referred to as the quality of seeing Amateur astronomers talk almost constantly about the seeing conditions since perhaps ironically even the clearest darkest skies may be almost worthless for serious observations if the air is not steady This steadiness of the atmosphere is most readily gauged by observing the twinkling of the stars rapid twinkling implies air motion in the Earth s atmosphere and under these conditions resolution of fine detail on the surface of Jupiter for instance will generally be limited When the air is steady stars appear to the naked eye as untwinkling points of unchanging brightness and it is in such a situation that the full potential of the telescope may be realized higher powers may be used to advantage closer double stars resolved as distinct points and fine detail observed on the Moon and planets OBSERVING GUIDELINES Several basic guidelines should be followed for best results in using your telescope 1 Try not to touch the eyepiece while observing Any vibrations re
6. 43X 324X UWA 6 7mm 182X 182X 170X 228X UWA 8 8mm 139X 139X 130X 173X UWA 14mm 87X 87X 81X 109X Not recommended for 10 and 12 5 models Should be used only under extremely steady atmospheric conditions Meade Super Pl ssl and Super Wide Angle Eyepieces are ideal for general purpose astronomical or terrestrial observing The typical Starfinder Dobsonian user may wish to add 2 or 3 of these eyepieces to his or her telescope An introductory selection might include the SP9 7mm and SP15mm The more advanced observer will perhaps select the SP 9 7mm SP 12 4mm and SWA 18mm The Super Wide Angle Eyepiece series yields extremely wide fields of view perfect for the examination of star fields diffuse nebulae or for terrestrial applications Under very steady seeing conditions Meade UWA 4 7mm and 6 7mm eyepieces present the widest fields of view obtainable at high powers and are excellent eyepieces for the Moon and planets Filters Thirteen color filters are available for significantly increased contrast and resolution of detail on the Moon and planets For example the 8803 blue filter effectively enhances the reddish colored detail on the surface of Jupiter These filters thread into the barrels of all standard 1 25 O D eyepieces and may also be used for eyepiece projection photography Illuminated Reticle Eyepiece Permits easy visibility of guiding crosslines even against the darkest skies The standard 702A double cross
7. INSTRUCTION MANUAL 6 8 10 amp 12 5 Starfinder Dobsonian Telescopes MEADE t Meade Instruments Corporation WARNING Never use the Starfinder Dobsonian telescope to look at the Sun Looking at or near the Sun will cause instant and irreversible damage to your eye Eye damage is often painless so there is no warning to the observer that damage has occurred until it is too late Do not point the telescope or its viewfinder at or near the Sun Do not look through the telescope or its viewfinder as it is Fig 1 The Meade Starfinder Dobsonian Telescope Captions for Fig 1 Contents 1 Focuser assembly 6 8 10 and 12 5 Starfinder 2 Eyepiece Dobsonian Telescopes 3 Viewfinder bracket IRGOGUELONS dd fair tsetse daos eei auteni patios 4 4 Viewfinder Parts Listing and Assembly 0 0000 e eee 4 5 Optical tube assembly Assembling the 4 6 Mirror cell Optical Tube Assembly 00000 e eee 5 7T Side board Attaching the FOCUSED 2 ra Re 5 8 Ground plate Attaching the Viewiinger Ney SHEER RPM 5 9 Base plate Installing the Primary Mirror 5 10 Front board Balancing the Telescopes au 0 xot e 6 The WING has abate sut eR Sem EU oe Gem Bo dene P 6 11 Altitude bearing Aligning the Viewfinder 0 s0ee0eeee 6 Using the Viewfinder 6 Collimation of the Optical System 6 Correct Collimation llle 7
8. Refer to Figure 3 You will note that there is a colored marker on the rear of the telescope tube There is a corresponding colored marker 8 Fig 3 on the mirror cell Carefully slide the mirror cell into the rear of the tube ensuring that the two colored markers line up Secure the cell to the tube with the four provided large headed screws 1 Fig 3 Again do not overtighten the screws A firm feel is sufficient 4 Carefully place the assembled optical tube into the previously assembled base as illustrated in Figure 1 Note that the two large bearings on the side of the tube 11 Fig 1 rest in the cutouts of the mount Also note the orientation of the tube to the mount the focuser 1 Fig 1 should be on the opposite side from the mount s Front Board 10 Fig 1 Fig 3 Installing the Primary Mirror in the Optical Tube Assembly 1 Attachment Bolts 2 Primary Mirror 3 Alignment Markers 4 Counterweight Thread 5 Collimation Bolts Fig 4 Newtonian Reflecting Telescope 1 Spider Vanes 2 Secondary Mirror 3 Parabolic Primary Mirror 4 Primary Mirror Hex Screws 8 Fig 4 and secondary mirror 2 Fig 4 are tilted so that the focused image 6 Fig 4 falls directly through the center of the focuser drawtube 5 Fig 4 To inspect the view of the mirror collimation remove the eyepiece and look down the focuser drawtube The round edge of the focuser drawtube 1 Fig 6 will frame the reflections o
9. coatings The aluminum coating on the primary and secondary mirrors may last more than ten years without significant deterioration The coatings will last a shorter period if regularly exposed to salty or polluted air Minor blemishes scratches or streaks will NOT impair the telescope s performance Re coating when necessary is relatively inexpensive Contact your local Meade dealer for information on mirror re coating services The most common error is to clean the optics too often If cleaning does become necessary clean as follows 1 Using distilled water and cotton gently swab the surface of the mirror to remove any dust or dirt Use the cotton to make one pass over the mirror and then use new cotton This will keep the dirt previously removed from contacting the mirror surface and scratching the coatings 2 Dip a wad of cotton in a mild detergent solution 1 2 teaspoon to 1 pint of water and gently swab the entire surface This will remove any oily deposits or fingerprints 3 Swab the entire surface Do not turn over the cotton wads or dissolved skin oils may deposit on the mirror s surface Immediately take a dry swab and continue wiping the entire surface gently Keep changing wads until the mirror surface is completely dry and free of streaks When cleaning the outside of the Starfinder optical tube 1 use a mild detergent Pine Sol Formula 409 Fantastic or oil soap Oil soap is preferred as it also acts as a pre
10. ed Most standard and optional accessories are interchangeable between the four telescopes For optimal enjoyment of the telescope please take a few minutes to read this manual and become familiar with all of the instrument s capabilities PARTS LISTING AND ASSEMBLY When first opening the packing boxes note carefully the following parts included with the Starfinder Dobsonian Telescope use Figure 1 and 2 to aid in the identification process Carton 1 The Telescope Optical tube assembly Primary mirror mounted in its cell Focuser Modified Achromat MA 25mm eyepiece 5 x 24mm viewfinder Hardware kit CAUTION The primary mirror must be handled with special care Never touch its reflective surface or place the mirror where it could be damaged Save all original packing materials if it is ever necessary to ship the telescope these materials will help to assure that no shipping damage will occur Carton 2 The Mount 2 Side boards Front board Ground plate Base plate 2 Handles Hardware kit Assembling the Mount Assembly of your Meade Starfinder Dobsonian telescope should only take a few minutes A phillips screwdriver pliers and an adjustable wrench are the only tools you will need 1 Attach the self adhesive rubber feet 11 Fig 2 to the underside of the ground plate 10 Fig 2 the round piece with the Teflon pads The feet should be mounted directly under the alread
11. er gently turn one or more of the three front most viewfinder alignment screws until the crosshairs of the viewfinder point at precisely the same position as the main telescope During this procedure occasionally look through the main telescope to make sure the object is still centered When the object is centered in the viewfinder confirm that the viewfinders crosshairs and the main telescope are now pointing at precisely the same object The viewfinder is now aligned to the main telescope Unless the alignment screws are disturbed the viewfinder will remain aligned indefinitely Using the Viewfinder Now to locate any object terrestrial or astronomical first center the object on the crosshairs of the viewfinder the object will then be centered in the field of the main telescope Note If you intend to use higher observing magnifications first locate center and focus the object using a low power eyepiece e g the 25mm eyepiece Objects are easier to locate and center at low powers higher power eyepieces may then be employed by changing eyepieces COLLIMATION OF THE OPTICAL SYSTEM Precise collimation or alignment of your telescope s optical system is essential for good performance All Meade telescopes are accurately collimated at the factory prior to shipment so collimation adjustments will probably not be necessary Nevertheless take the time now to familiarize yourself with the following collimation procedure so that y
12. f the primary mirror with the secondary mirror 2 Fig 6 the spider vanes 3 Fig 6 and your eye 4 Fig 6 Properly aligned all of these reflections will appear concentric i e centered as illustrated in Fig 6 Any deviation from the concentric reflections will require adjustments to the secondary mirror assembly Fig 5 and or the primary mirror cell Spider Vane Adjustments Looking down the open end of the telescope tube check to see if the secondary mirror system is centered in the optical tube If the assembly is off center loosen one of the spider vane adjustment lock knobs while unscrewing the opposite knob Only make adjustments to 2 knobs at a time until the secondary mirror is centered in the drawtube When the spider vane is correctly positioned the view through the drawtube will look like Fig 8 Secondary Mirror Misalignment 1 Secondary Mirror 2 Round Edge of Focuser Drawtube 3 Reflection of Primary Mirror Fig 9 Primary Mirror Misalignment 1 Secondary Mirror 2 Round Edge of Focuser Drawtube 3 Eye b Focuser Drawtube 6 Focused Image Face on view Edge on view Fig 5 Secondary Mirror Assembly 1 Spider Vanes 2 Tilt Screws 3 Secondary Mirror Holder Correct Collimation A properly collimated aligned mirror system in your Starfinder Dobsonian telescope assures the sharpest images possible Your Starfinder is properly aligned when the primary mirror Fig 6 Correc
13. hree primary mirror hex screws of the primary mirror cell These primary hex screws are located behind the primary mirror at the lower end of the main tube Adjust the primary mirror alignment by slightly turning one hex screw at a time looking through the focuser after each adjustment to determine if the mirror is moving in the correct direction Star Testing the Collimation With the collimation performed the next step is to test the accuracy of the alignment on a star Use the 25mm eyepiece and point the telescope at a moderately bright second or third magnitude star then center the star image in the telescope s field of view With the star centered follow the method below 1 Bring the star image slowly out of focus until one or more rings are visible around the central disc If the collimation was performed correctly the central star disk and rings will be concentric circles with a dark spot dead center within the out of focus star disk this is the shadow of the secondary mirror as shown in Fig 10A An improperly aligned telescope will reveal elongated circles Fig 10B with an off center dark shadow NM If the out of focus star disk appears elongated Fig 10B you will need to adjust the primary mirror tilt hex screws of the primary mirror cell Adjust the hex screw on the mirror cell until the circles are concentric on either side of focus Fig 10B TIPS ON USING A DOBSONIAN TELESCOPE Never lubricate the Tef
14. ler but brighter and sharper image is far more preferable to a larger but fuzzy indistinct one Viewfinders In addition to the standard equipment 5x24mm viewfinder supplied with all Starfinder telescopes the higher power larger aperture 6x30 and 8x50mm viewfinder are available to substitute or retrofit MEADE CUSTOMER SERVICE If you have a question concerning your Meade Starfinder Dobsonian telescope call Meade _ Instruments Customer Service Department at 949 451 1450 or fax at 949 451 1460 Customer Service hours are 8 30AM 4 00PM Pacific Time Monday through Friday In the unlikely event that your Dobsonian telescope requires factory servicing or repairs write or call the Meade Customer Service Department first before returning the telescope to the factory giving full particulars as to the nature of the problem as well as your name address and daytime telephone number The great majority of Starfinder servicing issues can be resolved by telephone avoiding return of the telescope to the factory Eyepiece 6 f 8 8 f 6 10 f 45 12 5 f 4 8 Power Power Power Power SP 6 4mm 191X 191X 178X 238X SP 9 7mm 126X 126X 118X 157X SP 12 4mm 98X 98X 92X 123X SP 15mm 81X 81X 76X 102X SP 20mm 61X 61X 57X 76X SP 26mm 47X 47X 44X 59X SP 32mm 38X 38X 36X 48X SP 40mm 31X 31X x i SWA 13 8mm 88X 88X 83X 111X SWA 18mm 68X 68X 63X 85X SWA 24 5mm 50X 50X 47X 62X SWA 32mm 38X 38X 36X 48X SWA 40mm 31X 31X UWA 4 7mm 260X 260X 2
15. line phosphorescent enhanced reticle allows for variable illumination from faint to very bright Magellan I The Magellan accessory will permit you to add a powerful pointing tool to your Starfinder Dobsonian telescope Encoders supplied with this product for the R A and Dec axis can be easily installed in factory machined mounting features Once installed the Magellan will allow the electronic selection and pointing of the telescope at a large number of catalogued objects in the sky 140 2x Barlow Lens The Barlow Lens or Telenegative Amplifier is a convenient accessory used to increase the effective magnification of any given eyepiece The Barlow Lens is inserted into the focuser and accepts all standard 1 25 O D eyepieces Specifications and Features Meade Starfinder Dobsonian Telescopes Starfinder Dobsonian 12 5 Newtonian Reflector 318mm 12 5 Grade A Pyrex glass fine annealed 4 vane steel 1525mm 1 4 8 0 36 15 0 17 4 0 95 inch 600X 0 89 x 1 27 15 1 x 58 long spiral wound Sonotube 2 60 4 3 26 75 25 square x 22 high Nylon Teflon 55 Ibs 41 Ibs 106 Ibs Starfinder Dobsonian 10 Starfinder Dobsonian 8 Starfinder Dobsonian 6 TELESCOPE Optical Design Newtonian Reflector Newtonian Reflector Newtonian Reflector Diameter Clear Aperture 152mm 6 203mm 8 254mm 10 Grade A Pyrex glass fine annealed Grade A Pyrex glass
16. lon pads on the ground plate The Meade Starfinder Dobsonian has been designed with some inherent friction You want the telescope to move easily when you position it but you also want it to stay in the position you place it Using any kind of oil silicone spray wax or grease will ruin the performance by causing the telescope to move too easily Just keep these bearing surfaces clean that s all the maintenance required N The altitude bearing surfaces 11 Fig 1 of the telescope are lightly lubricated at the factory for optimum performance Over a period of time these surfaces may become dry or dirty Simply clean off the bearing surfaces with a dry cloth or paper towel and reapply a thin coating of silicone grease or spray to the surfaces to maintain peak performance Do not use solvents or alcohol based As you use your telescope more and more you will find that you are seeing more and finer detail observing through a large aperture telescope is an acquired skill Celestial observing will become increasingly rewarding as your eye becomes better trained to the detection of subtle nuances of resolution CARE OF OPTICS AND MAIN TUBE With the reasonable care due any fine instrument your Meade telescope will last a lifetime If the eyepieces become dirty try cleaning them with a camel s hair brush or compressed air If you must wipe the surface of the lenses do so gently with a soft cloth so as not to scratch the protective
17. ou may recognize a properly collimated instrument and adjust the collimation yourself if necessary Optical Tube Assembly The optical tube has been pre drilled at the Meade factory to accept all standard accessories 1 Attaching the Focuser Lay the tube flat on the floor Align the holes in the focuser assembly 1 Fig 1 with the four pre drilled holes in the optical tube From the provided hardware place the four Phillips head screws through the holes Then carefully reach into the optical tube and attach a nut and washer to each screw Tighten the screws but do not overtighten tightening to a firm feel is sufficient 2 Attaching the Viewfinder With the optical tube lying flat on the floor align the two holes in the viewfinder bracket 8 Fig 1 with the pre drilled holes in the optical tube From the supplied hardware place a screw through each of the holes Carefully reach into the optical tube and attach a nut to each screw As with the focuser tightening to a firm feel is sufficient Overtightening may result in damage to the tube s finish Aligning the viewfinder is discussed later in this manual Your Meade Starfinder telescope was fully assembled aligned and tested at the Meade factory To ensure safe shipping the primary mirror was then removed from the telescope Locate the primary mirror cell assembly Fig 3 Again take extreme care not to touch or bump the primary mirror 3 Installing the Primary Mirror
18. ough the center of the ground plate This bolt should then be inserted through the center hole of the base plate 7 Fig 2 Secure this assembly with the other flat washer and the 5 16 locking nut 6 Fig 2 NOTE Do not overtighten the nut or the base plate will not easily rotate upon the ground plate Only tighten the pivot bolt and nut sufficiently to maintain a very light pressure between the ground plate and base plate The two parts should easily turn in a Lazy Susan fashion This completes assembly of your Meade Starfinder Dobsonian Mount Fig 2 Construction of the Dobsonian Mount 1 Handle 2 Screw Cover Caps 3 Wood Screws 4 Side Boards 5 Front Board 6 5 16 Locking Nut 7 Base Plate 8 Center Bearing Bushing 9 Nylon Washer 10 Ground Plate 11 Rubber Foot 12 2 14 x 5 16 Hex Pivot Bolt 13 Flat Washers INTRODUCTION The Starfinder Dobsonian telescope will open up the skies for a breathtaking array of visual observations Galaxies nebulae star clusters in all their variations of form color and extent as well as the Moon planets comets and other objects within the solar system may be studied in great detail This manual is designed for the 6 8 10 and 12 5 Starfinder Dobsonian Telescopes With the exception of a few assembly operations and features the four telescopes are almost identical operationally When differences in procedures occur they are clearly not
19. servative for the paint Solvent or alcohol based cleaning solutions will diminish the original luster of the paint OPTIONAL ACCESSORIES A wide assortment of professional Meade accessories is available for the Starfinder telescopes Dust Covers Snug fitting vinyl dust covers protect optics from outside dust during storage of the telescope Eyepieces Many additional eyepieces are available for higher and lower magnifications All Meade Starfinder Equatorial telescopes accept standard 1 25 O D eyepieces as well as 2 O D eyepieces Meade Super Pl ssl SP Super Wide Angle SWA and Ultra Wide Angle UWA Eyepieces in the standard American size 1 25 barrel diameter permit a wide range of magnifying powers with the telescope Powers obtained with each eyepiece are as follows detail than a dimmer poorly resolved larger image Because of certain characteristics of the human eye in particular eye pupil diameter and because of optical considerations inherent in the design of the telescope there exist minimum practical power levels also Generally speaking the lowest usable power is approximately 4X per inch of telescope aperture SEEING CONDITIONS Even in normal city conditions with all of the related air and light pollution there are many interesting celestial objects to observe But to be sure there is no substitute for the clear dark steady skies generally found only away from urban environments or on
20. sulting from such contact will immediately cause the image to move 2 Allow your eyes to become dark adapted prior to making serious observations Night adaptation generally requires about 10 15 minutes for most people 3 Let the telescope cool down to the outside environmental temperature before making observations Differences in temperature between a warm house and the cold outside air require about 30 minutes for the telescope s optics to regain their true correct figures During this period the telescope will not perform well 4 f you wear glasses and do not suffer from astigmatism take your glasses off when observing through the telescope You can re focus the image to suit your own eyes Observers with astigmatism however should keep their glasses on especially with lower powered eyepieces The effects of astigmatism are reduced with higher power eyepieces so eyeglasses may be removed to improve eye relief 5 Avoid setting up the telescope inside a room and observing through an open window or worse yet through a closed window The air currents caused by inside outside temperature differences will make quality observing impossible 6 Perhaps most important of all avoid overpowering your telescope The maximum usable magnification at any given time is governed by the seeing conditions If the telescopic image starts to become fuzzy as you increase in power drop down to a reduced magnification A smal
21. t Collimation 1 Round Edge of Focuser Drawtube 2 Secondary Mirror 3 Spider Vanes 4 Eye Fig 7 Spider Vane Misalignment 1 Secondary Mirror 2 Round Edge of Focuser Drawtube cleaning solutions as this may damage the bearings or the painted surfaces of the telescope 3 You will notice that your telescope will move in altitude by raising and lowering the tube and in azimuth by rotating the base As you observe objects in the night sky they will appear to drift out of the field of view due to the Earth s rotation To keep an object centered in the field of view just lightly nudge the telescope in the proper direction This may take a little practice at first but you ll soon get the hang of it 4 Be sure the Mount is placed on a relatively level surface to allow proper operation Each of the three feet should be in firm contact and not wobble If you are in an area with particularly rough or soft ground it may be helpful to place the Mount on a thick piece of plywood 5 Part of the fun of using a Dobsonian type of telescope is the challenge of hunting for objects in the night sky Invest is some simple star charts and books that tell you how to locate objects using a technique called star hopping Once you begin learning the star patterns and constellations you re well on you way to finding many amazing sights MAGNIFICATION The magnification or power at which a telescope is operating is determined by two
22. t in empty magnification where the object detail observed is actually diminished by the excessive power When beginning observations on a particular object start with a low power eyepiece get the object well centered in the field of view and sharply focused Then try the next step up in magnification If the image starts to become fuzzy as you work up into higher magnifications then back down to a lower power the atmospheric steadiness is not sufficient to support high powers at the time you are observing Keep in mind that a bright clearly resolved but smaller image will show far more Fig 8 Note that the secondary mirror is misaligned Secondary Mirror Adjustments If the secondary mirror 1 Fig 8 is centered in the drawtube 2 Fig 8 but the primary mirror is only partially visible in the reflection 3 Fig 8 the 3 hex screws located on the secondary mirror assembly 2 Fig 5 must be unthreaded slightly to refine the tilt angle of the secondary mirror until the entire primary mirror can be seen centered within the secondary mirror reflection When the secondary mirror is correctly aligned it will look like Fig 9 Note that the primary mirror is misaligned Primary Mirror Adjustments If the secondary mirror and the reflection of the primary mirror 1 Fig 9 appear centered within the drawtube 2 Fig 9 but the reflection of your eye 3 Fig 9 appears off center you will need to adjust one or more of the t
23. ut of balance This is a relatively easy problem to correct With a little ingenuity counterweights can be fashioned by the telescope owner using fishing sinkers or washers THE VIEWFINDER The Starfinder telescope as with almost all astronomical telescopes presents a fairly narrow field of view to the observer As a result it is sometimes difficult to locate and center objects in the telescope s field of view The viewfinder by contrast is a low powered wide field sighting scope with crosshairs that enables the easy centering of objects in the main telescope s field of view Standard equipment with the Starfinder telescope is a viewfinder of 5 power and 24 mm aperture called an 5 x 24mm viewfinder Aligning the Viewfinder In order for the viewfinder to be useful it must first be aligned with the main telescope so that both the viewfinder and the main telescope are pointing at precisely the same place To align the viewfinder follow this procedure 1 The viewfinder bracket includes six alignment screws Turn the three rear most alignment screws so that the viewfinder tube is roughly centered within the viewfinder bracket as viewed from the eyepiece end of the telescope 2 Using the standard equipment 25mm eyepiece point the main telescope at some easy to find well defined land object such as the top of a telephone pole Center the object precisely in the main telescope s field 3 While looking through the viewfind
24. y installed Teflon pads Two extra rubber feet have been supplied for use as bumpers where the telescope tube hits the front board 5 Fig 2 at the travel limits Place one in the center of the top ledge and one in the center on the inside near the bottom see Fig 2 The exact position for these two bumpers will be obvious with the telescope mounted on the base 2 Attach the front board 5 Fig 2 loosely to the two side boards 4 Fig 2 using the supplied wood screws 3 Fig 2 and the predrilled holes Do not fully tighten the screws yet 3 Attach the front board side board assembly to the base plate 7 Fig 2 using the supplied Wood Screws and the predrilled holes Snugly tighten all screws including those previously installed CAUTION Do not overtighten the wood screws The screws should be tightened sufficiently so that the head of the screw is flush with the wood surface BALANCING THE TELESCOPE Dobsonian telescopes are designed to move easily but at the same time remain in the position they are placed This is achieved by carefully balancing the telescope at the Meade factory The telescope is balanced for standard accessories However should anything attached to the telescope change for example using a larger or smaller eyepiece or even moving the primary mirror during collimation slight imperfections in balance may occur You may find as you change eyepieces or accessories that the telescope is o
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