Page 5 - Figure 1-1 Omni XLT 102 Refractor
- 5 - Figure 1-1 Omni XLT 102 Refractor (Omni XLT 102ED, Omni XLT 120 and Omni XLT 150R refractors are similar) 1. Optical Tube 7. 1.75" Steel Tripod 2. Tube Rings 8. Accessory Tray/ Leg Brace 3. Finderscope 9. Counterweights 4. Eyepiece 10. Counterweight Bar 5. Equatorial Mount 11. Dovetail Sli...
Page 6 - Figure 1-2 Omni XLT 150 Newtonian
- 6 - Figure 1-2 Omni XLT 150 Newtonian 1. Finderscope 7. 1.75" Steel Tripod 2. Finderscope Bracket 8. Accessory Tray/ Leg Brace 3. Focuser 9. Counterweights 4. Eyepiece 10. Counterweight Bar 5. Tube Rings 11. Dovetail Slide Bar 6. Equatorial Mount 12. Optical Tube 1 2 4 5 6 7 8 9 10 11 12 3
Page 7 - Figure 1-3 Omni XLT 127 Schmidt-Cassegrain
- 7 - Figure 1-3 Omni XLT 127 Schmidt-Cassegrain 1. Optical Tube 7. 1.75" Steel Tripod 2. Finderscope 8. Counterweights 3. Finderscope Bracket 9. Counterweight Bar 4. Equatorial Mount 10. Declination Setting Circle 5. Latitude Scale 11. Dovetail Slide Bar 6. Accessory Tray/ Leg Brace 12. Schmidt...
Page 8 - Figure
- 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...
Page 9 - attaches to the tripod head. On one side of the; DO NOT remove the
- 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...
Page 11 - Replace the counterweight safety screw.; Declination Shaft
- 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...
Page 12 - . Before you attach the optical; This will ensure that; Tube Rings
- 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...
Page 13 - Finderscope
- 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...
Page 14 - Slide the chrome portion of the eyepiece into the star diagonal.; Focuser Knob; Eyepiece; Visual Back
- 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...
Page 15 - GRADUALLY; — to see which way the telescope “rolls.”; DEC Clamp
- 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....
Page 16 - — to see which way it rotates around the declination axis.; DO NOT LET; Tighten the tube ring screws firmly to hold the telescope in place.
- 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...
Page 17 - NOT
- 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...
Page 18 - diagonal
- 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...
Page 19 - The
- 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...
Page 23 - The celestial sphere seen from the outside showing R.A. and DEC
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 ...
Page 26 - Definition; The position of the Big; Spring
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...
Page 27 - telescope and for casual; Polar Alignment with the Latitude Scale; tracking an object.; Big Dipper
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...
Page 28 - Pointing at Sigma Octantis; field of view of the finder.; SCP
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 ...
Page 31 - long as the motor drive is operating.; Here’s how to use the vernier:; the 18h 50m mark and the 19h 00m mark on the R.A. setting circle!
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...
Page 32 - Planetary Observing Hints
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...
Page 36 - See note about digital cameras below.
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...
Page 37 - even with a cable release
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...
Page 41 - DO NOT; Objective lens housing (with lens shade removed)
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...
Page 46 - Night Time Star Collimating; Procedure -- Please read this section completely before beginning.
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 ...
Page 48 - Omni Plössl; This 6 element design allows each X-Cel Eyepiece to have 20mm of; - Celestron offers four convenient filter sets, which
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...
Page 49 - Polar Axis Finderscope
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...
Page 51 - Appendix A Technical Specifications; Omni XLT Series
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...