Orion #10134 XT8g manuale d’uso

INSTRUCTION MANUAL IN 388 Rev . C 06/12 Customer Support (800 ) 676 -1 343 • E-mail: support@telescope.com Corporate Offices (831) 763-7000 • 89 Hangar W ay , Watsonville, CA 95076 © 2010-2012 Orion T elescopes & Binoculars Orion ® SkyQuest ™ XTg Go T o Dobsonians #10134 XT 8g, #10135 XT 1 0g, #10136 XT 1 2g Providing Exceptional Consum[...]

2 Figure 1. Ov er view of SkyQuest XTg Dobsonian (12" shown) Navigation knob Altitude motor housing 12.5mm Illuminated Plössl 1.25" ey epiece Eyepiece rac k Dobsonian base P olyeth ylene foam dust guard EZ Finder II 28mm DeepView 2" ey epiece 2" Dual-speed Cra yford f ocuser Optical tube Handle Handle T ube connecting knob GoT [...]

3 Congratulations on y our purchase of an Orion SkyQuest XTg GoT o Dobsonian. It is an obser ver’ s dream telescope, off ering quality diffraction-limited optics; a stylish, easy-to-setup base outfitted with automated, computerized Go T o technology; and a sturdy design. This high-performance astronomical instrument will provide dazzling views of[...]

4 Box #2: Dobsonian Base (Refer to Figures 3 and 4) Qty . Description 1 Left side panel (with altitude motor pre-installed) 1 Right side panel 1 F ront panel 2 Side braces (XT12g only , not shown) 1 Baseplate assembly (with azim uth motor pre-installed) 6 Base assembly w ood screws (coarse thread, 47mm long) (Quantity 12 f or XT12g) 8 Base assembly[...]

5 2. Assembly Now that y ou have unpac ked the bo xes and f amiliarized yourself with all the parts in front of you, it is time to begin assembly . Assembly of the Dobsonian Base The base need only be assembled once, unless y ou disas - semble it f or long-term storage. The assembly process should take about half an hour . All necessar y tools are [...]

6 3 . Carefully position the assembled structure onto the top baseplate by aligning the holes in the cutouts of the front and side panels to the corresponding threaded metal col- lar inser ts on the top baseplate (Figure 10). Inser t the base assembly machine scre ws and tighten (Figure 11). Once this setup is complete you ma y firmly tighten the s[...]

7 ing the six Phillips-head screws that connect the end ring to the tube (Figure 12), and then pulling the end ring off the tube. W arning: Once the rear end ring is remo ved from the tube, the raw edge of the tube itself will be exposed. Be careful not to cut or otherwise hurt yourself on the tubeís edge. Also, be careful not to pinc h your finge[...]

8 Connecting the Optical T ube to the Dobsonian Base The telescope is now assemb led and ready to be placed into the Dobsonian base. The left altitude hub on the optical tube has a dov etail slot that slides into the altitude axis tr unnion on the inside of the left side panel (Figure 17). W e recommend orienting the tr unnion such that the threade[...]

9 the dot, which is pur posefully quite dim. The intensity of the dot is adjusted by turning the power knob . F or best results when stargazing, use the dimmest possible setting that allo ws you to see the dot without difficulty . T ypically a dimmer set - ting is used under dark skies and a br ighter setting is needed under light-polluted skies or[...]

10 3. The GoT o Hand Controller The SkyQuest XTg f eatures the SynScan AZ hand controller, which provides two diff erent modes of operation: AutoT racking Mode The SkyQuest XTg base incor porates a quad-encoder design that records the position of the telescope relative to the sky . In the A utoT rac king mode, after a quick initial alignment pro - [...]

11 scope. The left and right directional b uttons can also be used to mov e the text cursor when entering data on the hand con- troller . Scroll Buttons The up and down scroll b uttons allow you to mo ve up and down within the menu tree or selections displa yed on the hand controller LCD . Dual Purpose buttons These buttons serve two distinct purpo[...]

12 must con vert into degrees and arcminutes. T o do this simply m ultiply the decimal value b y 60. If y our viewing location is at latitude 36.95 N y ou would enter a latitude of 36°57’ N [.95 x 60 = 57]. 6 . Enter the time zone in which y ou are obser ving in hours (see Appendix A) , using the scroll ke ys and numeric ke ypad (+ for east of P[...]

13 you choose will only aff ect your alignment star selection; you will still be ab le to choose stars to view across the entire sky once the alignment is complete. 3 . After you ha ve selected the region of the sky contain - ing the brightest star , the hand controller will generate a list of the brightest stars (magnitude 1.5 or br ighter and bet[...]

14 NO TE: When the power is on, y ou may choose to adjust the telescope electronicall y by using the hand control or manually b y pushing the tube with yo ur hand. The tele - scope will calculate the coordinates accor dingly and dis- play the inf ormation correctly on the hand controller . NO TE: The hand controlís bac klit display will become dim[...]

15 object could be a bright named star , a planet, or an object from the Messier , NGC, or IC catalogs , but not a star from the SA O catalog. 2 . Find the ref erence object in the hand controller database and command the telescope to “GoT o” the object. 3 . Once the telescope has stopped slewing, press ESC to return to any submenu . 4 . Press [...]

16 applications that need to communicate with the motor control board directly . Setup Functions The Setup functions allow y ou to change any system variable or inf or mation regarding location, time, date, and alignment configurations. T o access the Setup Functions, either press the SETUP button on the hand controller or browse to SETUP on the Ch[...]

17 is pointed. Y ou may press the scroll buttons to s witch between the diff erent coordinate options. Set Slew Limits: Allows y ou to set slewing limits of the GoT o base’ s altitude axis, to pre vent the optical tube from colliding with the base. When y ou press ENTER in the Set Slew Limits submenu, y ou may enable or disab le the slew angular [...]

18 Using the User Defined Database The GoT o system allows you to sa ve up to 25 objects in the User Defined Database. Y ou can sav e currently unknown objects, unidentifiab le objects, current comet and/or aster - oid positions, or y ou can make a custom list of your f av orite objects to view f or quick access . Saving an object to the database 1[...]

19 2 . The hand controller will displa y a list containing the clos- est known object in diff erent catalogs and its distance to the e xact location where the telescope is pointed. Use the scroll buttons to vie w these objects. 3 . Press ESC to e xit this function. Linking with a Computer The SkyQuest XTg can be connected to a computer via the supp[...]

20 6 . When the download is complete , the Fir mware Loader will displa y “Update Complete”. The firmware in the computerized GoT o hand controller has now been updated. Y ou can click on the “HC V ersion” button to confirm the new version n umber of the fir mware (and possib ly the database, b ut the hardware version will not change with i[...]

21 mirror and the tilt of the primar y mirror are the two collimation adjustments that will be done most often. If the entire primar y mirror reflection is not visible in the sec - ondar y mirror , as in Figure 25c, you will need to adjust the tilt of the secondar y mirror . This is done by alternately loosen - ing one of the three secondar y mirro[...]

22 Viewing with Eyeglasses If you w ear eyeglasses , you ma y be able to keep them on while you observe , if your ey epieces hav e enough eye relief to allo w you to see the whole field of vie w . Y ou can tr y this by looking through the ey epiece first with your glasses on and then with them off , and see if the glasses restr ict the view to only[...]

23 10. Astronomical Obser ving The SkyQuest XTg GoT o Dobsonian provides prodigious capability f or obser ving the many wonders of the heav ens, from the major planets to deep-space nebulas and galaxies . In this section we giv e you some astronomical obser ving tips and briefly summar ize what y ou can expect to see . Selecting an Observing Site S[...]

24 you’v e centered the object in the ey epiece, you can s witch to higher magnification (shor ter focal length e yepiece), if you wish. This is especially recommended f or small and br ight objects like planets and doub le stars. The Moon also takes higher magnifications well. Deep sky objects, ho wev er , typically look better at medium or low [...]

25 that you find an observing site well awa y from light pollution. T ake plenty of time to let your e yes adjust to the darkness. As you become more e xperienced and your obser ving skills get shar per , you will be ab le to ferret out more and more subtle details and structure from these fascinating objects . Beginners are often sur prised to dis[...]

26 SkyQuest XT8g Primar y mirror : 203mm diameter , parabolic, center-marked Focal length: 1200mm Focal r atio: f/5.9 Focuser: Dual-speed Crayf ord (11:1), accepts 2" and 1.25" ey epieces with included adapter Optical tube material: Rolled steel Azimuth bearing: Thr ust needle bearing Altitude bearing: Ball bear ing Eyepieces: 28mm DeepVi[...]

27 SkyQuest XT12g Primar y mirror : 305mm diameter , parabolic, center-marked Focal length: 1500mm Focal r atio: f/4.9 Focuser: Dual-speed Crayf ord (11:1), accepts 2" and 1.25" ey epieces Optical tube material: Rolled steel Azimuth bearing: Thr ust needle bearing Altitude bearing: Ball bear ing Eyepieces: 28mm DeepView , 2" barrel, [...]

28 Menu T ree[...]

29 Appendix A: Time Zones of the W orld[...]

30 Appendix B: RS-232 Connection The SkyQuest XTg Mount is designed to receive commands sent from a computer’ s RS-232 COM por t (via the computer interf ace cable). The hand controller will communicate with the computer at 9600 bits/sec, no parity , no stop bit. All angles are communicated with 16 bits and communicated using ASCII he xadecimal. [...]

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One-Y ear Limited W arranty The Orion XTg GoT o Dobsonians are warranted against def ects in materials or wor kmanship f or a per iod of one year from the date of purchase . This warr anty is for the benefit of the original retail purchaser only . During this warranty period Orion T elescopes & Binoculars will repair or replace, at Orion’ s o[...]