Celestron Omni XLT 102 - Manuals

- 8 - This section covers the assembly instructions for your Celestron Omni XLT telescope. The equatorial mount is exactly the same for all the Omni telescope models and the optical tubes have some differences which will be noted. Your Omni telescope should be set up indoor the first time so that it...

- 9 - A A t t t t a a c c h h i i n n g g t t h h e e E E q q u u a a t t o o r r i i a a l l M M o o u u n n t t The equatorial mount allows you to tilt the telescope’s axis of rotation so that you can track the stars as they move across the sky. The Omni mount is a German equatorial mount that att...

- 11 - Since the fully assembled telescope can be quite heavy, position the mount so that the polar axis is pointing towards north before the tube assembly and counterweights are attached. This will make the polar alignment procedure much easier. I I n n s s t t a a l l l l i i n n g g t t h h e e C...

- 12 - 5. The DEC slow motion knob attaches in the same manner as the R.A. knob. The shaft that the DEC slow motion knob fits over is toward the top of the mount, just below the telescope mounting platform. Once again, you have two shafts to choose from. Use the shaft that is pointing toward the gro...

- 13 - I I n n s s t t a a l l l l i i n n g g t t h h e e F F i i n n d d e e r r s s c c o o p p e e To install the finderscope onto the telescope you must first mount the finderscope through the finder bracket and then attach it to the telescope. Toward the rear of the telescope tube (on refracto...

- 14 - I I n n s s t t a a l l l l i i n n g g t t h h e e S S t t a a r r D D i i a a g g o o n n a a l l The Star Diagonal is a prism that diverts the light at a right angle to the light path of refractors and Schmidt-Cassegrain telescopes. This allows you to observe in positions that are physical...

- 15 - The refracting telescopes can use eyepieces and diagonals of a 2” barrel diameter. To use a 2” barrel eyepiece, the 1¼” eyepiece adapter must first be removed. To do this, simply loosen the two chrome thumbscrews located around the focuser barrel (see figure 2-12) and remove the 1 ¼” adapter....

- 16 - B B a a l l a a n n c c i i n n g g t t h h e e M M o o u u n n t t i i n n D D E E C C The telescope should also be balanced on the declination axis to prevent any sudden motions when the DEC clamp (Fig 2-13) is released. To balance the telescope in DEC (all telescopes except the SCT): 1. Re...

- 17 - A A d d j j u u s s t t i i n n g g t t h h e e M M o o u u n n t t i i n n A A l l t t i i t t u u d d e e • To increase the latitude of the polar axis, tighten the rear latitude adjustment screw and loosen the front screw (if necessary). • To decrease the latitude of the polar axis, tighten...

- 18 - A telescope is an instrument that collects and focuses light. The nature of the optical design determines how the light is focused. Some telescopes (known as refractors) use lenses and other telescopes, known as reflectors (Newtonians), use mirrors. Then, the Schmidt-Cassegrain telescope uses...

- 19 - Figure 3-3 A A c c u u t t a a w w a a y y v v i i e e w w o o f f t t h h e e l l i i g g h h t t p p a a t t h h o o f f t t h h e e S S c c h h m m i i d d t t - - C C a a s s s s e e g g r r a a i i n n o o p p t t i i c c a a l l d d e e s s i i g g n n The Schmidt-Cassegrain optical sys...

23 Up to this point, this manual covered the assembly and basic operation of your telescope. However, to understand your telescope more thoroughly, you need to know a little about the night sky. This section deals with observational astronomy in general and includes information on the night sky and ...

26 Figure 4-4 Remember, while Polar aligning, DO NOT move the telescope in R.A. or DEC. You do not want to move the telescope itself, but the polar axis. The telescope is used simply to see where the polar axis is pointing. Like the previous method, this gets you close to the pole but not directly o...

27 P P o o l l a a r r A A l l i i g g n n m m e e n n t t i i n n t t h h e e S S o o u u t t h h e e r r n n H H e e m m i i s s p p h h e e r r e e Polar alignment to the South Celestial Pole (SCP) is a little more challenging due to the fact that there is no very bright star close to it like Pol...

28 Pointing at Sigma Octantis This method utilizes Sigma Octantis as a guidepost to the celestial pole. Since Sigma Octantis is about 1° degree from the south celestial pole, you can simply point the polar axis of your telescope at Sigma Octantis.. Although this is by no means perfect alignment, it ...

31 8. Lock the R.A. clamp to prevent the telescope from slipping in R.A. The telescope will track in R.A. as long as the motor drive is operating. 9. Look through the finderscope to see if you have located the object and center the object in the finder. 10. Look in the main optics and the object sho...

32 With your telescope set up, you are ready to use it for observing. This section covers visual observing hints for solar system and deep sky objects as well as general observing conditions which will affect your ability to observe. O O b b s s e e r r v v i i n n g g t t h h e e M M o o o o n n Of...

36 4. Set the shutter speed to the “B” setting and focus the lens to the infinity setting. 5. Locate the area of the sky that you want to photograph and move the telescope so that it points in that direction. 6. Find a suitable guide star in the telescope eyepiece field of view. This is relatively e...

37 2. Center the Moon in the field of your telescope. 3. Focus the telescope by turning the focus knob until the image is sharp. 4. Set the shutter speed to the appropriate setting (see table 6-1). 5. Trip the shutter using a cable release. 6. Advance the film and repeat the process. Lunar Phase ISO...

41 While your telescope requires little maintenance, there are a few things to remember that will ensure your telescope performs at its best. Each optical design type has special collimation instructions described below. C C a a r r e e a a n n d d C C l l e e a a n n i i n n g g o o f f t t h h e e...

46 Night Time Star Collimating After successfully completing daytime collimation, night time star collimation can be done by closely adjusting the primary mirror while the telescope tube is on its mount and pointing at a bright star. The telescope should be set up at night and a star's image should ...

48 You will find that additional accessories for your Omni telescope will enhance your viewing pleasure and expand the usefulness of your telescope. This is just a short listing of various accessories. Visit the Celestron website for complete and detailed accessories available. Barlow Lens - A Barlo...

49 Flashlight, Night Vision - (# 93588) - Celestron’s premium model for astronomy, using two red LED's to preserve night vision better than red filters or other devices. Brightness is adjustable. It operates on a single 9 volt battery (included). Diagonal 2" Mirror (# 93519) - Celestron offers a...

51 Appendix A Technical Specifications Omni XLT Series 21088 21092 21090 21094 31057 11084 Omni XLT 102 Omni XLT 102ED Omni XLT 120 Omni XLT 150R Omni XLT 150 Omni XLT 127 Optical Design Refractor Refractor Refractor Refractor Newtonian Schmidt-Cassegrain Aperture 102mm (4.0") 102mm (4.0") 1...