Meade LXD55 Polar Alignment Viewfinder, Axis Alignment Procedure, Method 1 Manual Alignment

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Reticle LED Knob

Eyepiece

Fig. 36: The polar alignment viewfinder.

Fig. 37: The view inside the polar alignment viewfinder reticle.

Fig. 38: A. Elevation Alignment; B. Attitude Alignment.

APPENDIX B: ENHANCING POINTING PRECISION

The Polar Alignment Viewfinder

Typically Autostar's pointing capabilities are sufficient for most telescope observers, and the use of the polar alignment viewfinder is unnecessary for them. However, for those observers who need to meet the more demanding requirements of astropho- tography, the polar alignment viewfinder allows the telescope mount to be more pre- cisely aligned with true North. The polar alignment viewfinder contains a reticle, lit by an LED (Figs. 36 and 37).

To align your telescope to North using the polar alignment viewfinder:

1.Set your telescope in the home position (see page 17). Then loosen the Dec. lock (17, Fig. 1d) and rotate the optical tube 90°. Re-tighten the Dec. Lock.

2.Loosen the R.A. Lock (33, Fig. 1d).

3.Remove the polar viewfinder cap (18, Fig. 1d).

4.If you have not already done so, remove the plastic separating the watch batter- ies inside the polar alignment reticle. See step 12, page 13.

5.Turn the polar alignment reticle LED knob to turn on the LED and look through the reticle.

6.Northern Hemisphere: Move the telescope mount until Polaris is superimposed on the graduated area of the reticle (between 40' and 60'). The center crosshair denotes the North celestial pole. Southern Hemisphere: The four-sided figure in the reticle represents a grouping of four stars in Octantis (Sigma, Tau, Chi, and Upsilon) for use in the Southern Hemisphere. Move the telescope mount on its R.A. axis until the four stars depicted in the reticle are superimposed on the four star group that matches the reticle pattern.

7.Use the latitude T-handle screws (26, Fig. 1d) and the fine azimuth control knobs (27, Fig. 1d) to fine tune the mount adjustment until the reticle pattern is more precisely superimposed over the appropriate position as described in step 6.

Note: Not all pointing positions are possible with the polar alignment reticle, as the tripod is a limiting factor as to how far the optical tube and mount can be moved.

8.Tighten the R.A. Lock (33, Fig. 1d). Return the optical tube to the home position.

Note: Remember to turn off the polar alignment reticle LED.

Axis Alignment Procedure

In order for the equatorial mount to accurately point to astronomical objects using the GO TO feature of the Autostar handbox, the optical axis of the optical tube must be aligned with the R.A. axis of the mount. In most cases, the telescope will perform adequately without making any adjustments, but performing one of the following alignment methods before the initial use of the telescope, and periodically thereafter, will increase the mount’s pointing accuracy.

When the optical axis is perfectly aligned to the R.A. axis and the declination set to 90°, all objects will rotate about a point in the center of the eyepiece, as the mount is rotated about the R.A. axis. A misalignment in elevation results in the center of rotation shifting up or down. A misalignment in attitude results in the center shifting left or right.

The telescope is moved manually in Method #1 to correct for attitude misalignment and then for elevation misalignment. Autostar moves the telescope in Method #2; this method is recommended for beginners.

Method 1: Manual Alignment

Procedure #1: To correct for attitude misalignment

Important Note: Throughout the following procedures, the directional refer- ences up/down/left/right are used. No matter which type of telescope model you are using, these directions are to be interpreted relative to real-world targets. For example, left/right moves the image along the horizon, and up/down moves the image vertically.

Perform this procedure during the daytime. You will need to have a clear line of sight to a wide, distinct landmark with a clear, horizontal feature.

1.Plug in Autostar and turn on the power as described previously in this manual. You will use Autostar's Arrow keys in the course of this procedure.

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Contents Meade Instruments Corporation Page Contents Telescope Features 1 1% g f e$2% LXD55-SeriesYour Personal Window to the Universe Computer Control Panel see e LXD55 Tips Tour the Cosmos with Just the Push of a Button Autostar FeaturesFeatures Tip Accessories How to Assemble Your TelescopeTelescope Assembly Getting StartedViewfinder assembly Schmidt-Newtonian models Balancing the Telescope Insert eyepiece into holder and tighten thumbscrewsAligning the Viewfinder Choosing an EyepieceToo Much Power? Observing by Moving the Telescope ManuallyActivate the Arrow Keys Autostar Models Only Slew Speeds Autostar Models OnlyTracking Objects Setting the Polar Home PositionObserve the Moon 16bObserve a Star using the Automatic Tracking Feature Using Autostars GO to Capabilities Autostar Models OnlyMoving Through Autostar’s Menus Autostar Models Only Initializing Autostar Autostar Models OnlyTraining the Drive Autostar Models Only Easy Alignment Autostar Models Only Go To Saturn Autostar Models OnlyUsing the Guided Tour Autostar Models Only Planet Saturn is over 800 million miles from the EarthAutostar Navigation Exercise To Calculate Sunset timeEntering Data into Autostar Navigating AutostarAutostars Menus Select Item ObjectMenus Object MenuUtilities Menu Event MenuGlossary Menu LXD55-SeriesSetup Menu EnterObserving Considerations Setup Menu Daylight SAVING, Surf the Web To Edit a Site Adding Observing SitesTo Add a Site to the user-defined site list Using Autostar to Find Objects Not in the Libraries To GO to a user-entered objectTo Add a landmark to the database Observing SatellitesLandmarks To perform a Landmark Survey To Check on the Available MemoryTo Select a landmark from the database Photography Few tips on photography with the LXD55-SeriestelescopesOptional Accessories 10 f/4Series 4000 Photo-Visual Page Maintenance General MaintenanceD e f g Page Defocused star images. Misaligned 1, 2, Aligned Meade Customer Service Inspecting the Optics4 Model SN-8, SN-8EC Specifications Specifications5 Model SN-6, SN-6EC Specifications 8 Model AR-6 Specifications 10 f/4 Model SN-10 Specifications9.3 Model AR-5, AR-5EC Specifications Autostar Dimensions 10 Model SC-8 SpecificationsAutostar Specifications Setting Circles Appendix a Celestial CoordinatesOne-Star Polar Alignment Locating the Celestial PoleOne- and Two-Star Polar Alignment Two-Star Polar AlignmentPolar Alignment Viewfinder Axis Alignment ProcedureProcedure #1 To correct for attitude misalignment Method 1 Manual AlignmentProcedure #2 To correct for elevation misalignment Position aStar Charts TipsMethod 2 Axis Alignment Using Autostar City State/Prov./Country Latitude Appendix C Latitude ChartLatitude Chart for Major Cities of the World City Country LatitudeAppendix D EC Handbox Slew Speeds To move the telescope using the Electronic ControllerModes of Operation Tracking Rates Changing the Polar Mode Optional Autostar Computer Controller for LXD55 EC UsersHow to Attach the Optical Tube to the Mount Mounting the SC bracket and optical tube to the mountObjects in Space Appendix F Basic AstronomyAutostar Glossary MoonPlanets Deep-Sky ObjectsFurther Study Page Meade Instruments Corporation
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