Page 4 - Some of the many standard features of the CGE include:; Fully enclosed optical encoders for position location.
4 Congratulations on your purchase of the Celestron CGE telescope! The CGE ushers in the next generation of computer automated telescopes. T he Celestron CGE series continues in this proud tradition combining large aperture optics with the sophistication and ease of use of our computerized GoTo moun...
Page 5 - ASSE; - The CGE Telescope
5 ASSE 1 Schmidt Corrector Lens 8 Control Panel (see below) 2 Optical Tube 9 Hand Control Holder / Strap 3 Finderscope 1 0 Hand Control 4 Eyepiece 11 Tripod 5 Star Diagonal 1 2 Tripod Center Leg Brace 6 Declination Clutch Lock 1 3 Counterweights 7 Latitude Adjustment Scale 1 4 Counterweight Bar 1 5 ...
Page 6 - Setting up the Tripod
6 This section covers the assembly instructions for your Celestron CGE telescope. The CGE telescope should be set up indoors the first time so that it is easy to identify the various parts and familiarize yourself with the correct assembly procedure before attempting it outdoors. CGE 800 (# 11 058) ...
Page 7 - Place the lower end of the central column over the tripod head.; Tripod Leg
7 Attaching the Center Leg Brace For maximum rigidity, the Super HD Tripod has a center leg brace that installs on to the threaded rod below the tripod head. This brace fits snugly against the tripod legs, increasing stability while reducing vibration and flexure. To attach the center leg brace: 1. ...
Page 8 - Tighten the screws to hold the column securely in place.; Attaching the Equatorial Mount; Locate the opening in the equatorial mount on the DEC axis; Installing the Counterweight; Orient the mount so that the counterweight bar points toward the
8 5. Tighten the screws to hold the column securely in place. Attaching the Equatorial Mount After the tripod is set up, you are ready to attach the equatorial mount. The equatorial mount is the platform to which the telescope attaches and allows you to move the telescope in right ascension and decl...
Page 9 - Attaching the Optical Tube to the Mount; tight. This will ensure that the mount does not; Attaching the Visual Back
9 Dovetail Slide Bar Dovetail Locking Knobs Mounting Platform Figure 2-5 5. Tighten the locking screw on the side of the weight to hold the counterweight in place. 6. Replace the counterweight safety thumbscrew and washer. Attaching the Optical Tube to the Mount The telescope attaches to the mount v...
Page 10 - Slide the chrome portion of the eyepiece into the star diagonal.
10 Installing the Star Diagonal The star diagonal is a prism that diverts the light at a right angle to the light path of the telescope. This allows you to observe in positions that are physically more comfortable than if you looked straight through. To attach the star diagonal onto a CGE 800, 925 o...
Page 11 - Installing the Finderscope; Slide the eyepiece end of the finder into the front of the bracket.
11 focal length (i.e., the smaller the number) the higher the magnification. Generally, you will use low-to-moderate power when viewing. For more information on how to determine power, see the section on “Calculating Magnification.” Installing the Finderscope The CGE telescopes come with a 6x30 or 9...
Page 13 - Tighten the set screw on the counterweight to hold it in place.; Balancing The Mount in DEC; Tighten the R.A. clutch knobs to hold the telescope in place.; GRADUALLY; — to see which way it rotates around the declination axis.; DO NOT LET
13 Balancing The Mount in R.A. To eliminate undue stress on the mount, the telescope should be properly balanced around the polar axis. Proper balancing is crucial for accurate tracking. To balance the mount: 1. Verify that the telescope securing knobs on the telescope mounting platform are tight. 2...
Page 14 - v DC Power; Attaching the Motor Cables; DEC Port; Powering the Telescope; Optional Accessories; Transporting the CGE
14 On/Off Switch 1 2v DC Power Power Cord Strain Relief 5. Slightly loosen the knobs that holds the telescope to the mounting platform and slide the telescope either forward or backward until it remains stationary when the DEC clutch is loose. Do NOT let go of the telescope tube while the knob on th...
Page 15 - Note
15 6. Remove the center leg brace from the tripod. 7. Collapse the tripod legs inward, towards each other. The telescope is now broken down into enough pieces to be easily transported. Note : Before transporting the optical tube it is recommended that the two mirror locking screw located on the rear...
Page 16 - Has a dual-line, 16 character display screen that is backlit; The CGE Hand Control
16 The CGE has a hand controller designed to give you instant access to all the functions the CGE has to offer. With automatic slewing to over 40,000 objects, and common sense menu descriptions, even a beginner can master its variety of features in just a few observing sessions. Below is a brief des...
Page 18 - Alignment Procedures; Auto Two Star Alignment; Startup Procedure; Calibrating the CGE Mount; Press UNDO until
18 Alignment Procedures In order for the CGE to accurately point to objects in the sky, it must first be aligned to two known positions (stars) in the sky. With this information, the telescope can create a model of the sky, which it uses to locate any object with known coordinates. There are many wa...
Page 19 - Tip
19 (10) to scroll through the choices. Refer to Time Zone map in Appendix for more information. • Date - Enter the month, day and year of your observing session. • Finally, you must enter the longitude and latitude of the location of your observing site. Use the table in Appendix C to locate the clo...
Page 20 - Alignment Successful; Last Alignment
20 Quick-Align Quick-Align uses all the date and time information entered at startup to align the telescope. However, instead of slewing to two alignment stars for centering and alignment, the CGE bypasses this step and simply models the sky based on the information given. This will allow you to rou...
Page 21 - Object Catalog; speeds and may hit an observer in the eye.
21 Object Catalog Selecting an Object Now that the telescope is properly aligned, you can choose an object from any of the catalogs in the CGE's extensive database. The hand control has a key (4) designated for each of the catalogs in its database. There are two ways to select objects from the datab...
Page 22 - Tour Mode; Filter Limits; Direction Buttons
22 Tour Mode The CGE includes a tour feature which automatically allows the user to choose from a list of interesting objects based on the date and time in which you are observing. The automatic tour will display only those objects that are within your set filter limits (see Filter Limits in the Set...
Page 23 - Setup Procedures; Tracking Mode; EQ North; Off; Tracking Rate; Sidereal; Nine available slew speeds
23 up in the field of view of the eyepiece). However, if any of the slower slew rates (rate 6 and below) are used to center an object in the finderscope, you may need to press the opposite directional button to make the telescope move in the correct direction. 1 = .5x 6 = 64x 2 = 1x (sidereal) 7 = ....
Page 24 - User Defined Objects; GoTo Sky Obj; Identify; Helpful
24 sidereal time. Local sidereal time (LST) is useful for knowing the right ascension of celestial objects that are located on the meridian at that time. View Time-Site will always display the last saved time and location entered while it is linking with the GPS. Once current information has been re...
Page 25 - Precise GoTo; Precise Goto; Scope Setup Features
25 Named Object or Messier catalogs, the hand control will let you know that the Ring Nebula (M57) is approximately 6° from your current position. Searching the Double Star catalog will reveal that Epsilon Lyrae is only 1° away from Vega. To use the Identify feature: • Press the Menu button and sele...
Page 26 - Cone Value
26 button, go with the higher value for positive, but use a lower value for negative. CGE will remember these values and use them each time it is turned on until they are changed. Filter Limits – When an alignment is complete, the CGE automatically knows which celestial objects are above the horizon...
Page 27 - Calibrate Mount; Dec Switch / Cone Calibration; GoTo Calibration –; Move to Switch; Polar Align
27 • DEC Switch - This is the declination switch error value set when Utilities / Calibrate Mount / DEC Switch - Cone is carried out. • RA Switch - This is the R.A. switch error value set when Utilities / Calibrate Mount / R.A. Switch is carried out. Utility Features Scrolling through the MENU (9) o...
Page 28 - Light Control; Factory; Version
28 1. With the telescope set up and roughly positioned towards Polaris, align the mount using the AutoTwo- Star Alignment method. 2. Select Polar Align from the Utilities menu and press Enter. Based on your current alignment, the CGE will slew to where it thinks Polaris should be. Use the equatorial...
Page 30 - command functions; MENU; CGE Ready
30 CGE Menu Tree: The following figure is a menu tree showing the sub-menus associated with the primary command functions EQ NORTHEQ SOUTHOFF MODE SIDEREALSOLARLUNAR RAT E TRACKING VIEW TIME-SITE SETUP TIME-SITEANTI-BACKLASHFILTER LIMITSDIRECTION BUTTONSGOTO APPROACHAUTOGUIDE RATEMOUNT SETTINGS SCOP...
Page 31 - Image Orientation
31 Figure 4- 1 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 Actual image orientation as seen with...
Page 32 - Calculating Magnification; Focal Length of Telescope; Determining Field of View; Apparent Field of Eyepiece
32 Figure 4-3 The emblem on the end of the focus knob shows the correct rotational direction for focusing the CGE . Focusing The CGE's focusing mechanism controls the primary mirror which is mounted on a ring that slides back and forth on the primary baffle tube. The focusing knob, which moves the p...
Page 33 - a linear field width of 34.7; feet at a distance of; General Observing Hints
33 To convert degrees to feet at 1,000 yards, which is more useful for terrestrial observing, simply multiply by 52.5. Continuing with our example , multiply the angular field .66 ° by 52.5. This produces a linear field width of 34.7 feet at a distance of one thousand yards. The apparent field of ea...
Page 34 - The Celestial Coordinate System; The celestial sphere seen from the outside showing R.A. and DEC
34 Up to this point, this manual covered the assembly and basic operation of your CGE 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...
Page 35 - Motion of the Stars
35 Motion of the Stars The daily motion of the Sun across the sky is familiar to even the most casual observer. This daily trek is not the Sun moving as early astronomers thought, but the result of the Earth's rotation. The Earth's rotation also causes the stars to do the same, scribing out a large ...
Page 36 - Set the telescope up so that the polar axis is pointing north.
36 Latitude Scales The easiest way to polar align a telescope is with a latitude scale. Unlike other methods that require you to find the celestial pole by identifying certain stars near it, this method works off of a known constant to determine how high the polar axis should be pointed. The Celestr...
Page 37 - Finding the North Celestial Pole; Definition
37 2. Loosen the DEC clutch knob and move the telescope so that the tube is parallel to the polar axis. When this is done, the declination setting circle will read +90°. If the declination setting circle is not aligned, move the telescope so that the tube is parallel to the polar axis. 3. Adjust the...
Page 38 - Declination Drift Method of Polar Alignment; If the star drifts south, the polar axis is too far east.
38 Declination Drift Method of Polar Alignment This method of polar alignment allows you to get the most accurate alignment on the celestial pole and is required if you want to do long exposure deep-sky astrophotography through the telescope. The declination drift method requires that you monitor th...
Page 39 - Observing the Moon; lunar; Lunar Observing Hints
39 With your telescope set up, you are ready to use it for observing. This section covers visual observing hints for both solar system and deep sky objects as well as general observing conditions which will affect your ability to observe. Observing the Moon Often, it is tempting to look at the Moon ...
Page 41 - Seeing; Figure; conditions produce images that lie some where
41 Seeing Seeing conditions refers to the stability of the atmosphere and directly affects the amount of fine detail seen in extended objects. The air in our atmosphere acts as a lens which bends and distorts incoming light rays. The amount of bending depends on air density. Varying temperature laye...
Page 42 - Short Exposure Prime Focus Photography; are some film recommendations:
42 After looking at the night sky for a while you may want to try photographing it. Several forms of celestial photography are possible with your telescope, including short exposure prime focus, eyepiece projection, long exposure deep sky, terrestrial and even CCD imaging. Each of these is discussed...
Page 43 - Eyepiece Projection; even with a cable release
43 • T-Max 400 • Any 100 to 400 ISO color slide film • Fuji Super HG 400 • Ektar 25 or 100 2. Center the Moon in the field of your CGE 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 below). 5. Trip ...
Page 44 - Long Exposure Prime Focus Photography
44 act as a shutter. The card prevents light from entering the telescope while the shutter is released. Once the shutter has been released and the vibration has diminished (a few seconds), move the black card out of the way to expose the film. After the exposure is complete, place the card over the ...
Page 46 - Using Periodic Error Correction; PEC
46 Using Periodic Error Correction Once the telescope has been properly polar aligned, select PEC from the Utilities menu and press ENTER to begin recording your periodic error. Here’s how to use the PEC function. 1. Find a bright star relatively close to the object you want to photograph. 2. Insert...
Page 47 - Terrestrial Photography; Your; CGE makes an excellent; Metering; the Vibration Suppression Pads.; These pads rest between the ground and; CCD Imaging
47 • Konica 3200 (color print) • Fujichrome 1600D (color slide) • 3M 1000 (color slide) • Scotchchrome 400 • T-Max 3200 (black and white print) • T-Max 400 (black and white print) As you perfect your technique, try specialized films, that is films that are designed or specially treated for celestial...
Page 49 - Focal
49 F as tar L ens A s s em bl The key factors for good CCD imaging are; exposure time, field-of-view, image size, and pixel resolution. As the F/# goes down (or gets faster), the exposure times needed decreases, the field-of-view-increases, but the image scale of the object gets smaller. What is the...
Page 50 - Medium size to small galaxies –; The Dumbbell
50 with a 30 second exposure and can be improved upon dramatically if several 30-60 second exposures are added together . F/6.3 with Reducer/Corrector When imaging some objects like planetary nebula (for example M57, the Ring Nebula) and small galaxies (M104, the Sombrero Galaxy), larger image scale...
Page 51 - Auto Guiding
51 Auto Guiding The CGE telescope has a designated auto guiding port for use with a CCD autoguider. The diagram below may be useful when connecting the CCD camera cable to the CGE and calibrating the autoguider. Note that the four outputs are active-low, with internal pull-ups and are capable of sin...
Page 52 - Care and Cleaning of the Optics; Do NOT rub in circles!; Collimation; collimation is
52 While your CGE telescope requires little maintenance, there are a few things to remember that will ensure your telescope performs at its best. Care and Cleaning of the Optics Occasionally, dust and/or moisture may build up on the corrector plate of your telescope. Special care should be taken whe...
Page 53 - that the central obstruction of the star image is skewed.
53 Figure 8-3 A collimated telescope should appear symmetrical with the central obstruction centered in the star's diffraction pattern. To accomplish this, you need to tighten the secondary collimation screw(s) that move the star across the field toward the direction of the skewed light. These screw...
Page 54 - Celestron and Software Bisque have joined together to; hart printing, zoom capability; This accessory is an Amici prism arrangement; OMNI Plössl; our; Axiom
54 You will find that additional accessories enhance your viewing pleasure and expand the usefulness of your telescope. For ease of reference, all the accessories are listed in alphabetical order. Adapter AC (#18773) - Allow DC (battery powered) telescopes to be converted for use with 120 volt AC po...
Page 55 - Fastar Lens Assembly; Filters
55 Fastar Lens Assembly – (#94 1 80 – 8", #94 1 79 – 11 ", #94 1 8 1 - 1 4 ) - For the ultimate in deep-sky imaging, a Fastar Lens Assembly can be combined with any of Celestron's Fastar compatible telescope to achieve amazing f/2 wide-field images. Celestron offers the lens assembly complet...
Page 64 - Communication Protocol:; Description
64 Appendix B - RS-232 Connection You can control your CGE telescope with a computer via the RS-232 port on the computerized hand control and using an optional RS-232 cable (#93920). Once connected, the CGE can be controlled using popular astronomy software programs. Communication Protocol: CGE-i co...
Page 65 - Additional RS232 Commands; The number 35 is returned from the handcontrol
65 Additional RS232 Commands S S e e n n d d A A n n y y T T r r a a c c k k R R a a t t e e T T h h r r o o u u g g h h R R S S 2 2 3 3 2 2 T T o o T T h h e e H H a a n n d d C C o o n n t t r r o o l l 1. Multiply the desired tracking rate (arcseconds/second) by 4. Example: if the desired trackra...
Page 66 - APPENDIX C – MAPS OF TIME ZONES
Page 74 - CELESTRON TWO YEAR WARRANTY
CELESTRON TWO YEAR WARRANTY A. Celestron warrants this telescope to be free from defects in materials and workmanship for two years. Celestron will repair or replace such product or part thereof which, upon inspection by Celestron, is found to be defective in materials or workmanship. As a condition...
