Instruction Manual 8" LX90 Schmidt-Cassegrain Telescope AutoStar® — LNT™ — SmartFinder™
The Meade Schmidt-Cassegrain Optical System (2) (1) (1) (2) Ray (2) Ray (1) (2) (1) Focal Plane Secondary Mirror Secondary Baffle Primary Baffle Tube Field Stops Primary Mirror Correcting Plate In the Schmidt-Cassegrain design of the Meade LX90, light enters from the right, passes through a thin lens with 2-sided aspheric correction (“correcting plate”), proceeds to a spherical primary mirror, and then to a convex secondary mirror.
CONTENTS WARNING! Never use a Meade® LX90 Telescope to look at the Sun! Looking at or near the Sun will cause instant and irreversible damage to your eye. Eye damage is often painless, so there is no warning to the observer that damage has occurred until it is too late. Do not point the telescope at or near the Sun. Do not look through the telescope or SmartFinder as it is moving. Children should always have adult supervision while observing.
QUICK-START GUIDE It is recommended that you attach the supplied tripod to the LX90 for observing. Perform the telescope and AutoStar setup indoors in the light so that you become familiar with the parts and operation before moving the telescope outside into the dark for observing. 1 1. 4 Remove the field tripod from the shipping carton. Stand the tripod vertically with the tripod feet down and with the tripod still fully collapsed.
6 Battery Compartment 9 Rib Slew Speeds: Speed 9: Fast . Arrow . . Keys Speed 5: Medium . . . Speed 1: Slow Number Keys 9. Battery Holder 6. Remove the covers from both battery compartments located on top of the drive base and carefully lift the battery holders from their compartments, being mindful of the connector wires. Insert four (user-supplied) C-cell batteries into each battery holder (eight batteries total), oriented as shown on the diagram on the battery holder.
TELESCOPE FEATURES Side View C B 7 9 S P M J D A E M A. B. C. D. E. (not shown) Q L Handbox Port LED ON/OFF Switch Auxiliary Ports (2) 12v Power Connector Computer Control Panel O 5 D R 2! 2) K 6 A 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Eyepiece Eyepiece Holder Thumbscrew Eyepiece Holder Diagonal Prism Optical Tube Dec. Lock Fork Arms Focus Knob R.A. Lock R.A. Setting Circle Dec. Setting Circle/Dec.
LX90: Your Personal Window to the Universe The Meade LX90 is an extremely versatile, high-resolution telescopes with features similar to those available only with larger and more specialized imaging systems. With pushbutton controls, automatic tracking of celestial objects and software downloading capability, the LX90 telescope may be all the telescope ever required by many terrestrial and astronomical observers.
D. Auxiliary (AUX) Port (2): Provides connection for the LNT module, and also current and future Meade accessories, such as the Meade Accessory Port Module. See “OPTIONAL ACCESSORIES,” page 41. E. 12v Power Connector: Provides connection so that the telescope assembly may be powered from either a 12v DC auto cigarette light plug or from a standard 115v AC home outlet using optionally available 25' power cords. N AutoStar: See page 9 for a description of AutoStar’s features.
AUTOSTAR FEATURES L 1 D B E C H F G K I J Fig. 2: The LX90 AutoStar Handbox. Tour the Cosmos with Just the Push of a Button Control of the LX90 is through the operation of the standard-equipment AutoStar. Nearly all functions of the telescope are accomplished with just a few pushes of AutoStar’s buttons.
NOTE: AutoStar does not require batteries; the telescope’s batteries supply power to AutoStar. The AutoStar Computer Controller provides control of virtually every telescope function within a compact handbox. AutoStar has soft-touch keys designed to have a positive feel. The LCD (Liquid Crystal Display) is backlit with a red LED (Light Emitting Diode) for easy viewing in the dark. The backlit display, key arrangement, and sequential database make AutoStar extremely user friendly.
8. The SmartFinder’s red dot will now blink on for 10.2 seconds and turn off for 0.7 seconds, and then repeat the cycle until you change the values again. Press and hold MODE c to exit this function. Similarly, you can set the Intensity value by scrolling through the intensity values with the Scroll keys h. The Intensity option lets you select a value of intensity for the red dot from 0 (Off) to 14 (Full Intensity).
GETTING STARTED Getting the telescope ready for first observations requires only a few minutes. When first opening the packing box, note carefully the following parts: • • • • • • • LX90 Telescope with fork mount system and attached SmartFinder AutoStar handbox and interface coil cord Eyepiece holder and 1.
6. Place the entire telescope onto the top of the tripod head, and insert the threaded rod into the central hole in the bottom of the drive base of the telescope. Tighten the tension knob (3, Fig. 3); firm tightening of the tension knob is sufficient to result in rigid positioning of the tripod legs. 7. To vary the tripod height, loosen the 6 lock-knobs, slide the 3 inner tripod leg sections out to the desired height, and firmly re-tighten (but do not overtighten) the 6 lock-knobs.
Choosing an Eyepiece A telescope’s eyepiece magnifies the image formed by the telescope’s main optics. Each eyepiece has a focal length, expressed in millimeters, or “mm.” The smaller the focal length, the higher the magnification. For example, an eyepiece with a focal length of 9mm has a higher magnification than an eyepiece with a focal length of 26mm.
Aligning SmartFinder In order for the SmartFinder to be useful, it must first be aligned with the main telescope, so that both the SmartFinder and the main telescope are pointing at precisely the same location. To align the SmartFinder: 1. Point the main telescope at some well-defined distant (perhaps a mile away) land object, such as a telephone pole or sign. Center the object, as precisely as possible, in the SP 26mm eyepiece's field of view. Tighten the vertical and horizontal locks (6 and 9, Fig.
OBSERVING IMPORTANT NOTE: Objects appear upside-down and reversed left-for-right when observed in the eyepiece when inserted directly into the (straight-through) eyepiece holder – with the diagonal prism in place, images will be right-side-up, but reversed left-for-right. This image inversion is of no consequence when observing astronomical objects and, in fact, all astronomical telescopes yield inverted images.
2. 3. Verify that AutoStar is properly connected to your telescope. See “HOW TO ASSEMBLE YOUR TELESCOPE,” page 13. Flip the telescope power switch to the ON position. The AutoStar screen is activated and a copyright message displays briefly, followed by a short beep. Then AutoStar takes a few moments to start up the system. 4. 5. A message displays that warns not to look at the Sun. At the end of this message, press the key prompted by AutoStar to signify that the message has been read and understood.
Astronomical Observing Used as an astronomical instrument, your telescope has many optical and electromechanical capabilities. It is in astronomical applications where the high level of optical performance is readily visible. The range of observable astronomical objects is, with minor qualification, limited only by the observer’s motivation. To Track an Object Automatically As the Earth rotates beneath the night sky, the stars appear to move from East to West.
NOTE: AutoStar requests the Zip Code or the Country/State, City, and Telescope Model information only the first time AutoStar is activated. If you wish to change this information, use the "Site" and "Telescope Model" options in the Setup menu. See page 30 for more information. IMPORTANT NOTE: While performing the automatic tracking procedure, only use the Arrow keys to move the telescope. Once the telescope has been set in the Alt/Az home position, do not loosen the telescope locks (6 and 9, Fig.
However, when the telescope slews to the first star, it may not appear in the field of view in the eyepiece. Use the SmartFinder (17, Fig. 1) and /or the viewfinder (1, Fig. 20) to locate the star. The alignment star will be easy to recognize—it will be the brightest star in the area of the sky where the telescope is pointing. Look through the SmartFinder or the viewfinder and use the Arrow keys to move the telescope until the star is visible.
BASIC AUTOSTAR OPERATION OBJECT Select from over 30, 220 database objects and press GO TO to move the telescope automatically to the object and place it in the telescopic field of view. SETUP Quick, easy alignment permits all telescope operations with only a 2-minute setup. Select Item: Object Select Item: Setup UTILITIES Calculate eyepiece magnifications; set the timer for an observing session; or change the display brightnes.
To 1. 2. 3. 4. 5. 6. 7. 8. 9. Calculate Sunset time: Press the MODE key several times, until “Select Item: Object” is displayed. Press the Scroll Down key once to display the “Event” option in the “Select Item” menu. Press the ENTER key to choose the "Event" option and move down a level. "Event: Sunrise" is displayed. Press the Scroll Down key once to display the "Sunset" option in the Event menu. Press the ENTER key to choose the "Sunset" option and move down another level.
Tonight's Best How Far is Far A Star's Life Downloaded Tours User-created Tours Tour Objects Select Item: Guided Tour Accretion Disk Etc. B... C... D... E... F... G... H... I... J... K... L... M... N... O... P... Q... R... S... T... U... V... W... X... Y... Z... A... Select Item: Glossary Note: The SmartFinder menu (for setting the blink rate and intensity of SmartFinder’s red dot) is only accessible by pressing and holding the Mode key for two seconds. See pages 10 and 14.
MENUS AND MENU OPTIONS Use the OBJECT menu to select an object from the database. When your telescope is aligned and you select an object from any of these lists, you just need to press the GO TO key to move the telescope so that it is pointed at the selected object. Over 30,000 objects are available for the LX90. The available objects include planets, constellations, individual stars, double stars, star clusters, galaxies, quasars, satellites, asteroids and comets.
Use the Event menu to look up dates of various astronomical events, such as sunrises and sunsets, eclipses, moon phases, meteor showers, equinoxes and solstices... ...and not just for the current date. Set any date, past or future, when initializing AutoStar and you can check the time for other events. Use the Glossary menu to look up definitions of astronomical terms and get a description of AutoStar features. Event Menu The Event menu provides access to dates and times of astronomical events.
J Set: Enter the time of day for the alarm to sound, in hours, minutes, and seconds, then press ENTER. J Start/Stop: Activates the alarm set previously. Use the Scroll keys to toggle between ON and OFF. When ON is displayed, press ENTER to activate the alarm. When the alarm time arrives, AutoStar beeps. Press ENTER to deactivate the alarm. Eyepiece Calc calculates information about an eyepiece for the specific telescope to which AutoStar is connected.
Park Scope is designed for a telescope that is not moved between observing sessions. Align the telescope one time, then use this function to park the telescope. Next time it is powered up, enter the correct date and time – no alignment is required. Pressing ENTER causes the telescope to move to its pre-determined Park position. Once parked, the screen prompts to turn off power.
J Reverse L/R: Reverses the functions of the Left and Right Arrow keys (i.e., the Right key moves the telescope to the left). J Reverse UP/DOWN: Reverses the functions of the Up and Down Arrow keys (i.e., the Up key moves the telescope down). J Calibrate Sensors: This menu allows you to improve your telescope's pointing accuracy to alignment stars. It calibrates to correct slight mechanical misalignment due to transport, vibration, or aging.
NOTE: AutoStar compensates for daylight savings time, if selected. See “SETUP MENU: DAYLIGHT SAVING,” page 27. Owner Info accesses the owner information menu, including: J Name: Users may enter both their first and last names using the Up and Down Arrow keys to cycle through the alphabet. Use the Right and Left Arrow keys to move through the text. Press ENTER when the entry is complete. J Address: Use the Up and Down Arrow keys to enter your street address, city, state, and zip code.
ADVANCED AUTOSTAR FEATURES Adding Observing Sites If you plan to observe using AutoStar at different geographic locations, you can store up to six observation sites in AutoStar's memory to help simplify your telescope setup. Perform these procedures using the Site options (Add, Select, Delete, Edit) of the Setup menu. To Add a Site to the user-defined site list: In this example, you will choose a city and add it to the database list. You will then select the site to enable it. 1. 2. 3. 4. 5. 6.
Time Zone Atlantic Eastern Central Mountain Pacific Hawaii Shift -4 Hours -5 Hours -6 Hours -7 Hours -8 Hours -10 Hours Table 1: Time Zone Shift. TIP: Entering R.A. and Dec Coordinates of an object without using the menus: If you do not wish to navigate through the menus, a more direct way to enter coordinates is to press and hold MODE for two seconds or more. R.A. and Dec coordinates display. Press GO TO. "Object Position" and a set of coordinates displays. Enter the R.A.
9. AutoStar then prompts you to enter the magnitude of the object. This step is also optional. Use the Number keys to enter this information, if so desired, and press ENTER to go to the next display. "User Object: Add" displays again. To GO TO a user-entered object: In this procedure, you will choose an object from the User Object list and GO TO the object. 1. With "User Object: Add" displayed, press the Scroll Up key once. "User Object: Select" displays. Press ENTER. 2.
How to Create Your Own Guided Tour When a Guided Tour is selected, AutoStar slews your telescope to a predetermined list of objects and displays information about each object, such as type of object, constellation location, R.A. and Dec coordinates, and so forth. AutoStar contains a few Guided Tours which are programmed at the factory. But it is also possible for an observer to create a custom Guided Tour. A tour is basically an ASCII text file that contains a list of directions and descriptions.
Writing a Tour Using the list of commands listed above, a custom tour can be created. Placing the word AUTO SELECT before any of the command lines activates Automatic Mode and, when selected, AutoStar automatically searches and finds the designated object. The following is a list of command lines, complete with keywords and necessary strings: TITLE Title must be the first keyword in your tour after any comment lines and must be 15 characters or less.
ASTEROID "name" Enter ASTEROID and then the name of the desired asteroid in quotes. AutoStar displays information about the asteroid from its database. For example: ASTEROID: "Ceres" COMET "name" Enter COMET and then the name of the desired comet in quotes. AutoStar displays information about the comet from its database.
AUTO SLEW ON / AUTO SLEW OFF With AUTO SLEW ON enabled in the tour, AutoStar automatically slews the telescope to objects first before displaying the text description. This feature is useful when designing tours in which observing certain objects is required. For example, an astronomy professor may require his students to observe six objects, four of which AutoStar automatically slews to in a tour. The students would have to manually slew to the last two objects.
2. Display the "Landmark: Select" menu option. Press ENTER. 3. Use the Scroll keys to scroll through the list of objects you have previously entered. When the desired object displays, press ENTER to select the object. Use the Scroll keys to scroll through location information about the object, if desired. Press GO TO to slew the telescope to the landmark. 4. Press MODE to exit.
North Two-Star Alt/Az Alignment Two-Star Alignment requires some knowledge of the night sky. AutoStar provides a database of bright stars and two stars from this database are chosen by the observer for alignment. Note: If you choose “Easy Align,” Autostar will choose the two alignment stars. 1. 2. 3. 0° Fig. 13: Alt/Az Home Position. Initialize your telescope, as described on page 18. With "Align: Automatic" displayed, press one of the Scroll keys until "Align: Two Star" displays. Press ENTER.
PHOTOGRAPHY WITH THE LX90 2 Photography through the LX90 requires the addition of the optional #62 T–Adapter. See “OPTIONAL ACCESSORIES,” page 39. With the #62 T-Adapter and a T-mount attached to the telescope (Fig. 14), through-the-telescope photography is possible with any 35mm camera body with a removable lens. In this way, the telescope effectively becomes the lens of the camera. 1 The #62 T-Adapter (1, Fig. 14) threads on to the photo port, followed by a T-Mount (2, Fig.
Shorter exposure times is one of the biggest drawback. Long exposures with digital cameras introduce undesirable noise and artifacts into a digital image. This limits the range of astro images to the Moon, planets and bright stars. Some tips for better digital photos: • • • • • • • • • • • If you cannot remove the lens to your camera, look for a commercially available digital T-adapter. New solutions for attaching a digital camera to a telescope are becoming available as time goes by.
OPTIONAL ACCESSORIES A wide assortment of professional Meade accessories is available for the LX90 telescope. The premium quality of these accessories is well-suited to the quality of the instrument itself. Consult the Meade General Catalog for complete details on these and other accessories. Some of the Meade Series 4000 and 5000 Eyepieces are as follows. For a complete list, see you Meade Dealer:* Magnifying With #140 Power 2x Barlow Eyepiece Super Plössl (4-elements) SP 6.4mm 313X SP 9.7mm 206X SP 12.
#62 T-Adapter: The T-Adapter (Fig. 22) is the basic means of prime-focus photography through all Meade Schmidt-Cassegrain models. Thread the T-Adapter on to the rear cell of your telescope, followed by a T-Mount for your 35mm camera, and the camera body is rigidly coupled to the telescope. Variable Tele-Extender: For eyepiece-projection photography of the Moon and the planets, a Tele-Extender is required.
MAINTENANCE The LX90 is a precision optical instrument designed to yield a lifetime of rewarding applications. Given the care and respect due any precision instrument, the LX90 will rarely, if ever, require factory servicing. Maintenance guidelines include: a. Avoid cleaning the telescope’s optics: a little dust on the front surface of the telescope’s correcting lens causes virtually no degradation of image quality and should not be considered reason to clean the lens. b.
ring of light fills about 10% of the eyepiece field-diameter. If the dark central spot is offset in (i.e., not concentric with) the ring of light, your telescope’s optical system is misaligned and requires collimation. Follow these steps for collimation of the optical system: a. The only adjustments possible, or necessary, on the LX90 are from the three screws (Fig. 25) located at the edge of the outer surface of the secondary mirror housing.
Inspecting the Optics A Note About the “Flashlight Test:" If a flashlight or other high-intensity light source is pointed down the main telescope tube, the view (depending upon the observer’s line of sight and the angle of the light) may reveal what appears to be scratches, dark or bright spots, or just generally uneven coatings, giving the appearance of poor quality optics.
LX90 Specifications Optical design ............................................................Schmidt-Cassegrain Clear aperture ............................................................8" Focal length ................................................................2000mm Focal ratio (photographic speed) ..............................f/10 Resolving power..........................................................0.56 arc secs Viewfinder....................................................................
APPENDIX A: EQUATORIAL (POLAR) ALIGNMENT Polar Alignment In Polar Alignment, the telescope is oriented so that the horizontal and vertical axes of the telescope are lined up with the celestial coordinate system. In order to Polar align your telescope, it is essential to have an understanding of how and where to locate celestial objects as they move across the sky.
Locating the Celestial Pole To get basic bearings at an observing location, take note of where the Sun rises (East) and sets (West) each day. After the site is dark, face North by pointing your left shoulder toward where the Sun sets. To precisely point at the pole, find the North Star (Polaris) by using the Big Dipper as a guide (Fig. 29). For precise tracking of astronomical objects, your telescope should be Polar aligned. Little Dipper Big Dipper Polaris Cassiopeia Fig. 29: Locating Polaris.
Note that the R.A. circle is double-indexed (i.e., there are two series of numbers running in opposite directions around the circumference of the R.A. circle). The upper series of numbers (increasing counterclockwise) applies to observers located in the Earth’s Northern Hemisphere; the lower series of numbers (increasing clockwise) applies to observers located in the Earth’s Southern Hemisphere. Fig. 30: Section of Right Ascension Setting Circle.
Begin polar aligning the telescope by locating Polaris. Finding Polaris is simple. Most people recognize the “Big Dipper.” The Big Dipper has two stars that point the way to Polaris (Fig. 29). Once Polaris is found, it is a straightforward procedure to obtain a rough polar alignment. To line up with Polaris, follow the procedure described below.
1. Obtain a rough polar alignment as described earlier. Place the illuminated reticle eyepiece (or eyepiece/Barlow combination) into the eyepiece holder of the telescope. 2. Point the telescope, with the motor drive running, at a moderately bright star near where the meridian (the North-South line passing through your local zenith) and the celestial equator intersect. For best results, the star should be located within ±30 minutes in R.A.
APPENDIX B: HELPFUL CHARTS Latitude Chart for Major Cities of the World To aid in the Polar Alignment procedure (see page 46), latitudes of major cities around the world are listed below. To determine the latitude of an observing site not listed on the chart, locate the city closest to your site. Then follow the procedure below: Northern Hemisphere observers (N): If the site is over 70 miles (110 km) North of the listed city, add one degree for every 70 miles.
APPENDIX C: TRAINING THE DRIVE Train the telescope motors using AutoStar. Perform this procedure if you are experiencing any pointing accuracy problems. Fig. 31 depicts the complete Drive Training procedure. NOTE: Use a terrestrial object, such as a telephone pole or lamp post, to train the drive. Complete this exercise once every 3 to 6 months to 1 2 Verify that AUTOSTAR INITIALIZATION is complete. Press MODE until Select Item is displayed. Select Item Object Further Study....
Top Alignment screw Side Alignment screw APPENDIX D: CHANGING THE LNT MODULE BATTERY The LNT Module uses a lithium coin CR2023 battery that will last about 5 years and is installed with the original LNT Module assembly. After you replace the battery, you will need to recalibrate the telescope’s sensors and reset the time and date. You will need a new battery. Also, you may use Meade’s optional Atomic Time Update Module, although this is not necessary. To replace the battery: Fig.
APPENDIX E: BASIC ASTRONOMY In the early 17th century Italian Scientist Galileo, using a crude telescope considerably smaller than the LX90, turned it to look towards the sky instead of distant trees and mountains. What he saw, and what he realized about what he saw, forever changed the way mankind thought of the universe.
Planets Planets change positions in the sky as they orbit around the Sun. To locate the planets on a given day or month, consult a monthly astronomy magazine, such as Sky and Telescope or Astronomy. You can also consult AutoStar for information about planets. Scroll to the "Object: Solar System" menu and scroll through the lists of planets. When a planet you are interested in displays, press ENTER.
MEADE LIMITED WARRANTY Every Meade telescope, spotting scope, and telescope accessory is warranted by Meade Instruments Corporation (“Meade”) to be free of defects in materials and workmanship for a period of ONE YEAR from the date of original purchase in the U.S.A. and Canada. Meade will repair or replace a product, or part thereof, found by Meade to be defective, provided the defective part is returned to Meade, freight-prepaid, with proof of purchase.
