Meade LX90GPS instruction manual Precise Polar Alignment

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Tip:

You can check if the Declination is set at true 90° in step 2c. Look through the eyepiece and rapidly slew the optical tube on the R.A. axis. If all the stars rotate around the center of the field of view, the Declination is set at 90°. If the stars arc out of the field of view, slew the optical tube on the Declination axis until you achieve the centering effect.

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. Refer to the instruction sheet included with your equatorial wedge for information about attaching the wedge to the telescope and also about using the azimuth and latitude controls.

1.Select "Setup: Telescope" from the AutoStar menus. Press ENTER. Scroll to "Telescope:

Mount" and press ENTER. Scroll to "Scope Mounting: Polar" and press ENTER. The tele- scope mount is now set to the polar mode.

2.Press MODE until "Select Item: Setup" displays. Press ENTER. "Setup: Align" displays.

Press ENTER. Scroll to "Align: One-Star" and press ENTER. AutoStar now prompts you to set the telescope in the polar home position.

a.Using the bubble level of the wedge, adjust the tripod legs so that the bubble is level.

b.Set the wedge to your observing latitude.

c.Using the Up and Down Arrow keys, rotate the telescope tube in Declination so that the telescope’s Declination reads 90°, that is the molded Dec pointer (11, Fig. 1) is pointed to 90° on the Dec. setting circle.

d.Loosen the R.A. lock, and rotate the fork arms to the 00 position H. A. on the R.A. setting circle.

e.Press ENTER. The telescope slews to Polaris.

f.Use the azimuth and latitude controls on the wedge to center Polaris in the field of view. Do not use the AutoStar handbox during this process. When Polaris is centered, press ENTER. The telescope is now polar aligned.

At this point, your polar alignment is good enough for casual observations. There are times, however, when you will need to have precise polar alignment, such as when making fine astrophotographs.

Once the latitude angle of the wedge has been fixed and locked-in according to the above procedure, it is not necessary to repeat this operation each time the telescope is used, unless you move a considerable distance North or South from your original observing position. (Approximately 70 miles movement in North-South observing position is equivalent to 1° in latitude change.) The wedge may be detached from the field tripod and, as long as the latitude angle setting is not altered and the field tripod is leveled, it will retain the correct latitude setting when replaced on the tripod.

The first time you polar align the telescope, check the calibration of the Declination setting circle (11, Fig. 1). After performing the polar alignment procedure, center the star Polaris in the telescope field. Remove the knurled central hub of the Declination setting circle and move the setting circle so that the molded triangular pointer to 90°.

Precise Polar Alignment

It should be emphasized that while doing casual observing, precise alignment of the telescope’s polar axis to the celestial pole is not necessary. Don’t allow a time-consuming effort at lining up with the pole to interfere with your basic enjoyment of the telescope. For long-exposure photography, however, the ground rules are quite different, and precise polar alignment is not only advisable, but almost essential.

Even though the LX90 telescopes offers a sophisticated drive system, the fewer tracking cor- rections required during the course of a long-exposure photograph, the better. (“Long-exposure” means any photograph of a celestial object that last for 10 minutes or longer). In particular, the number of Declination corrections required is a direct function of the precision of polar alignment.

Precise polar alignment requires the use of a crosshair eyepiece. The Meade Illuminated Reticle Eyepiece (see OPTIONAL ACCESSORIES, page 43) is well-suited in this application, but it is also preferable to increase the effective magnification through the use of a 2X or 3X Barlow lens as well. Follow this procedure (particularly if the pole star is not visible), sometimes better known as the “Drift” method:

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Contents 10, 12 LX90GPS Schmidt-Cassegrain Telescopes Meade Schmidt-Cassegrain Optical System Contents QUICK-START Guide ON/OFF E D Telescope FeaturesComputer Control Panel LX90 Your Personal Window to the UniverseTo Attach the Handbox Holder Tour the Cosmos with Just the Push of a Button Autostar FeaturesTopmost screen Select Item Object Down, left, and right, at any Slew SPEEDS, page 17. Getting Started How to Attach the Tripod to the Telescope AssemblyPrecautionary notes for the tripod How to Assemble Your TelescopeChoosing an Eyepiece Using SmartFinderAligning the Viewfinder Aligning SmartFinderObserving Observing Using AutoStars Arrow KeysObserving By Moving the Telescope Manually Terrestrial ObservingObserve the Moon Slew SpeedsTo Track an Object Automatically Astronomical ObservingMoving Through AutoStar’s Menus To prepare your telescope for Automatic AlignmentImportant Tip Observe a Star using the Automatic Tracking FeatureGo To Saturn Using the Guided TourLX90 Tips Global Positioning System AutoStar Navigation Exercise Basic Autostar OperationTo Calculate Sunset time Entering Data into AutoStarNavigating AutoStar Select Item Object Menus and Menu OptionsObject Menu Utilities Menu Event MenuGlossary Menu Observing Considerations Setup Menu Page Delete Deletes a stored site from the database Adding Observing Sites Advanced Autostar FeaturesTo Add a Site to the user-defined site list To Edit a SiteUsing AutoStar to Find Objects Not in the Database To GO to a user-entered object Observing SatellitesCommand Line How to Create Your Own Guided TourWhat you will need Tour ModesTitle Writing a TourPick END Downloading Tours LandmarksTo Add a landmark to the database To Select a landmark from the databaseAlternate Alt/Az Alignments IdentifyTo perform a Landmark Survey To check on the available amount of memory in AutoStarEasy Two-Star Alignment How to perform the Easy Align ProcedureTwo-Star Alt/Az Alignment To Set the Home Position ManuallyBrowse One-Star Alt/Az AlignmentPhotography with a Digital Camera Photography with the LX90Few tips on photography with the LX90 Meade Deep Sky Imager Photography with Meade’s AutoStar SuiteEyepiece Power 2x Barlow Super Plössl 4-elements Optional AccessoriesSuper Wide Angle 6-elements Ultra Wide Angle 8-elements#62 T-Adapter Collimation MaintenancePage Gauging the Movement of the Telescope Meade Consumer Solutions ServiceInspecting the Optics 10 LX90 Specifications LX90 SpecificationsAutoStar Dimensions 12 LX90 SpecificationsAutoStar Specifications Celestial Coordinates Polar AlignmentLocating the Celestial Pole Setting CirclesAutoStar Polar Alignment Easy Polar AlignmentEquatorial Wedge Lining Up with the Celestial PolePrecise Polar Alignment Follow these steps City State/Prov./Country Latitude Latitude Chart for Major Cities of the WorldCity Country Latitude City State/Country LatitudeAppendix C Training the Drive Moon AutoStar GlossaryObjects in Space Deep-Sky Objects PlanetsPage Meade Limited Warranty

LX90GPS specifications

The Meade LX90GPS is a premium telescope that offers both amateur and seasoned astronomers a powerful and user-friendly platform for exploring the night sky. This telescope blends advanced technology with robust design, making it one of the preferred choices for stargazers around the globe.

One of the standout features of the LX90GPS is its Advanced Coma-Free (ACF) optics. This design minimizes spherical aberration and eliminates off-axis coma, ensuring sharp, high-contrast images across the entire field of view. Coupled with a large aperture of 8, 10, or 12 inches, users can enjoy stunning views of celestial objects including planets, galaxies, and nebulae.

The telescope is equipped with a fully automated GoTo system that simplifies the hunting of celestial objects. The built-in GPS makes for effortless location setting, locking onto satellites and positioning the telescope accurately. Once set up, users can access a database containing over 30,000 celestial objects, allowing for easy navigation and exploration.

In addition to its exceptional optics and GoTo capabilities, the LX90GPS features Smart Mount technology. This innovative system incorporates adjustments based on real-time sky data, ensuring that the telescope remains aligned with celestial bodies as they move across the night sky. The LX90GPS also includes a unique Auto-Alignment feature, where a simple two-star alignment procedure helps calibrate the telescope quickly and easily.

The design of the LX90GPS is user-centric, combining functionality with comfort. The telescope comes with an easy-to-operate control panel and a large, multi-line LCD screen that displays critical information. Users can easily manage various functions and settings without fumbling through complex menus.

Additional features include the option for removable optical tubes, allowing for easy upgrades or repairs. The telescope is compatible with a variety of Meade accessories, including focal reducers and filter sets, enhancing its versatility for different observing conditions.

In conclusion, the Meade LX90GPS stands out for its remarkable optics, user-friendly technology, and impressive range of features. Whether you’re gazing at the Moon, tracking planets, or delving into deep-sky observations, the LX90GPS provides a fulfilling astronomical experience that inspires exploration and delight in the universe.
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