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Omni XLT Series Telescopes
Omni XLT Series Telescopes
INSTRUCTION MANUAL
INSTRUCTION MANUAL
● Omni XLT 102 ● Omni XLT 120 ● Omni XLT 150 ● Omni XLT127
● Omni XLT 102 ● Omni XLT 120 ● Omni XLT 150 ● Omni XLT127
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T Ta ab blle e o of f C Co on nt te en nt ts s INTRODUCTION .......................................................................................................................................................... 4 Warning...................................................................................................................................................... 4 ASSEMBLY ................................................................................................
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Using the Lens Cap Aperture Stop with Refractor Telescopes ................................................................ 32 ASTROPHOTOGRAPHY ........................................................................................................................................... 33 Piggyback Photography............................................................................................................................ 33 Short Exposure Prime Focus Photography for Refractors & Newto
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Congratulations on your purchase of an Omni XLT Series telescope. The Omni XLT Series of telescopes come in several different models --- 102mm refractor, 120mm refractor, 150mm Newtonian, 127mm Schmidt-Cassegrain. The Omni Series is made of the highest quality materials to ensure stability and durability. All this adds up to a telescope that gives you a lifetime of pleasure with a minimal amount of maintenance. Furthermore, your Celestron telescope is versatile — it will grow as
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1 12 2 3 11 4 5 10 6 9 7 8 Figure 1-1 Omni XLT 102 Refractor (Omni XLT 120 Refractor 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 Slide Bar 6. Latitude Adjustment Screw 12. Objective Lens Shad
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1 2 3 4 12 5 11 6 10 7 9 8 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
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1 12 2 3 11 10 4 9 5 8 6 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
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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 is easy to identify the various parts and familiarize yourself with the correct assembly procedure before attempting it outdoor. Each Omni telescopes comes in two boxes. One box contains the
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Attaching the Equatorial Mount Attaching the Equatorial Mount 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 attaches to the tripod head. On one side of the tripod hea
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Attaching the Center Leg Brace Attaching the Center Leg Brace Tripod Mounting Knob Central Rod Accessory Tray Accessory Tray Knob Exhibit 2-6 1. Remove the accessory tray knob and washer from the central rod. 2. Slide the accessory tray over the central rod so that each arm of the tray is pushing against the inside of the tripod legs. 3. Thread the acc
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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. IIn ns st ta alllliin ng g t th he e C Co ou un nt te er rw we eiig gh ht ts s
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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 ground. This makes it easy to reach while looking through the telescope, something which is quite important when you are observing but again if it is more convenient for you to use, then reinstall th
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Installing the Finderscope Installing the Finderscope 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 refractors and Schmidt-Cassegrain) and front of the telescope tube (Newtonian), there is a small bracket with a set screw in it. This is where the finderscope bracket will be mounted. To install the finderscope: 1. Loosen the finderscope adj
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Installing the Star Diagonal Installing the Star Diagonal 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 physically more comfortable than if you looked straight through. Eyepiece To attach the star diagonal onto the optical tube of a Schmidt- Cassegrain: 1. Turn the set screw on the visual back until its tip no longer extends into (i.e., obstru
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The refracting telescopes can use eyepieces and diagonals of a 2” barrel diameter. To use a 2” barrel eyepiece, the 1 ¼” 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. Once removed, a 2” eyepiece or accessory can be inserted directly into the focuser barrel and secured with the two thumb screws. Eyepieces are commonly referred to by focal length and
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Balancing the Mount in DEC Balancing the Mount in DEC 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: 1. Release the R.A. clamp and rotate the telescope so that it is on one side of the mount (i.e., as described in the previous section on balancing the telescope in R.A.). 2. Lock the R.A. clamp to hold the telescope in place. 3. Release the DEC clamp and rotat
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Adjusting the Mount in Altitude Adjusting the Mount in Altitude • 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 the front (under the counterweight bar) latitude adjustment screw and loosen the rear screw (if necessary). The latitude adjustment on the Omni mount has a range from approximately 20° going up to 60°. It is best to always mak
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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. Other telescopes, known as reflectors (Newtonians), use mirrors. Then, the Schmidt-Cassegrain telescope uses both mirrors and lenses. Each optical design is briefly discussed below: eveloped in the early 1600s, the refractor is the oldest telescope design. It derives its name from the method it us
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Figure 3-2 A A c cu utta aw wa ay y v viie ew w o of f tth he e lliig gh htt p pa atth h o of f tth he e N Ne ew wtto on niia an n o op pttiic ca all d de es siig gn n The Schmidt-Cassegrain optical system (or Schmidt-Cass for short) uses a combination of mirrors and lenses and s referred to as a compound or catadioptric telescope. This unique design offers large-diameter optics while maintaining very short tube lengths, making them extrem
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Image Orientation Image Orientation The image orientation changes depending on how the eyepiece is inserted into the telescope. When using the star diagonal with refractors and Schmidt-Cassegrains, the image is right-side-up, but reversed from left-to-right (i.e., mirror image). If inserting the eyepiece directly into the focuser of a refractor or the visual back of the Schmidt-Cassegrain (i.e., without the star diagonal), the image is upside-down and reversed from left-to-right (
