Meade LXD 75-Series instruction manual

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Alignment (Collimation) of the Newtonian Reflector Optical System

The optical systems of Newtonian Reflector telescopes include the following parts: pri- mary mirror (1, Fig. 34); secondary mirror (2, Fig. 34); secondary mirror-holder (3, Fig. 34); secondary mirror-vanes (4, Fig. 34) and (1, Fig. 35); primary mirror-tilt screws (5, Fig. 34). The telescope’s image is brought to a focus at (6, Fig. 34).

1.Confirm alignment - To confirm optical alignment look down the focuser draw- tube (1, Fig. 37) with the eyepiece removed. The edge of the focuser drawtube frames reflections of the primary mirror (2, Fig. 37), the secondary mirror (3, Fig. 37), the three (“spider”) vanes (4, Fig. 37) holding the secondary mirror, and the observer’s eye (5, Fig. 37). With the optics properly aligned, all of these reflec- tions appear concentric (centered), as shown in Fig. 37. Any deviation from con- centricity of any of these telescope parts with the eye requires adjustments to the secondary mirror-holder (Fig. 35) and/or the primary mirror cell (Fig. 36, as described below.

2.Secondary mirror-vane adjustments: If the secondary mirror (1, Fig. 38) is left or right of center within the drawtube (2, Fig. 38), slightly loosen the 3-vane adjust- ment/lock knobs (1, Fig. 35) located on the outside surface of the main tube and slide the entire secondary mirror-holder system up or down in the slotted holes of the main tube until the secondary mirror is centered in the drawtube. If the secondary mirror (1, Fig. 38) is above- or below-center within the drawtube, thread inward one of the adjust- ment/lock knobs (1, Fig. 35) while unthreading another of these knobs. Only make adjustments to two knobs at a time until the secondary mirror appears as in Fig. 39.

3.Secondary mirror-holder adjustments: If the secondary mirror (1, Fig. 39) is cen- tered in the focuser drawtube (2, Fig. 39), but the primary mirror is only partially vis- ible in the reflection (3, Fig. 39), the three “+” (Phillips head) secondary mirror-tilt screws (2, Fig. 35) should be slightly unthreaded to the point where the secondary mirror-holder (3, Fig. 35) can rotate about its axis parallel to the main tube. Grasp the secondary mirror-holder (avoid touching the mirror surface!) with your hand and rotate it until, looking through the drawtube, you can see the primary mirror centered as well as possible in the reflection of the secondary mirror. With the rotation of the secondary mirror-holder at this best-possible position, thread in the three Phillips head screws (2, Fig. 35) to lock the rotational position. Then, if necessary, make adjustments to these three Phillips head screws to refine the tilt-angle of the second- ary mirror, until the entire primary mirror can be seen centered within the secondary mirror’s reflection. With the secondary mirror thus aligned the image through the drawtube appears as in Fig. 40.

4.Primary mirror adjustments: If the secondary mirror (1, Fig. 40) and the reflection of the primary mirror (2, Fig. 40) appear centered within the drawtube (3, Fig. 40), but the reflection of your eye and the reflection of the secondary mirror (4, Fig. 40) appear off-center, then the primary mirror tilt requires adjusting, using the Phillips head screws of the primary mirror cell (3, Fig. 36). These primary mirror-tilt screws are located behind the primary mirror, at the lower end of the main tube. See Fig. 36. Before adjusting the primary mirror-tilt screws, first unscrew by several turns (use either a hex wrench or pliers) the three hex-head primary mirror lock screws (2, Fig. 36) which are also located on the rear surface of the primary mirror cell and which alternate around the cell’s circumference with the three Phillips head screws. Then by trial and error turn the primary mirror Phillips head tilt screws (3, Fig. 36) until you develop a feel for which way to turn each screw to center the reflection of your eye in the drawtube. (An assistant is helpful in this operation.) With your eye centered as shown in Fig. 37, turn the three hex head primary mirror lock screws (2, Fig. 36) to re-lock the tilt-angle of the primary mirror.

The telescope’s optical system is now aligned, or collimated. This collimation should be re-checked from time to time, with small adjustments (per steps 1, 2, and/or 3, above) effected as required to keep the optics well-aligned.

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Contents LXD 75 -Series Telescopes Page Contents Telescope Features BC1 g f eD E F LXD75-SeriesYour Personal Window to the Universe $ Computer Control Panel see e LXD75 Tips Tour the Cosmos with Just the Push of a Button Autostar FeaturesFeatures Tip How to Assemble Your Telescope Telescope AssemblyAccessories Getting StartedViewfinder assembly Newtonian reflector models C D E F Balancing the TelescopeAligning the Viewfinder Choosing an EyepieceToo Much Power? Observing by Moving the Telescope ManuallyActivate the Arrow Keys Autostar Models Only Slew Speeds Autostar Models OnlySetting the Polar Home Position Observe the MoonTracking Objects 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 MenuEvent Menu Glossary MenuUtilities Menu LXD75-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 with Meade’s Autostar Suite PhotographyFew tips on photography with the LXD75-Seriestelescopes Optional Accessories 10 f/4Series 4000 Photo-Visual Optional Autostar handbox for EC model users Maintenance General MaintenanceD e f g Page Defocused star images. Misaligned 1, 2, Aligned Page Page 4 Model SN-8AT, SN-8EC Specifications Specifications5 Model SN-6AT, SN-6EC Specifications 8 Model AR-6AT Specifications 10 f/4 Model SN-10AT Specifications9.3 Model AR-5AT, AR-5EC Specifications 10 Model SC-8AT Specifications 5 Model N-6EC SpecificationsAutostar Specifications Autostar DimensionsMeade Customer Service Inspecting the OpticsSetting Circles Appendix a Celestial CoordinatesLocating the Celestial Pole Polar AlignmentOne-Star Polar Alignment Two-Star Polar AlignmentMethod #1 Three-Star Alignment Using Autostar Polar Alignment ViewfinderEnhancement Methods To perform the Three-Star AlignmentMethod 2 Axis Alignment Procedures Procedure #1 To correct for attitude misalignmentProcedure #2 To correct for elevation misalignment Position aMethod 3 Axis Alignment Using Autostar TipsMethod #4 Smart Drive Training Periodic Error Correction PEC Update Menu OptionPEC Train Menu Option PEC Erase Menu OptionAppendix C Latitude Chart Latitude Chart for Major Cities of the WorldCity State/Prov./Country Latitude 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 LXD75 EC UsersHow to Attach the Optical Tube to the Mount Mounting the SC bracket and optical tube to the mountAppendix F Basic Astronomy Autostar GlossaryObjects in Space MoonPlanets Deep-Sky ObjectsFurther Study Page Meade Limited Warranty

LXD 75-Series specifications

The Meade LXD 75-Series telescopes represent a significant advancement in amateur astronomy technology, combining ease of use with professional-grade features. Designed for both novice and experienced astronomers, the LXD 75-Series offers sophisticated tracking capabilities and a range of optical tube assemblies, making it a versatile choice for stargazers.

One of the most notable features of the LXD 75-Series is its advanced German equatorial mount, which provides precise tracking of celestial objects. This mount is equipped with digital setting circles and a built-in autoguider port, allowing users to take long-exposure astrophotography without the hassle of manual adjustments. The telescope's mount is designed to be sturdy yet lightweight, enhancing portability for backyard observations or remote excursions.

The optical tube assemblies available in the LXD 75-Series include both refractor and reflector designs, allowing astronomers to choose according to their preferences. Refractors provide crisp, high-contrast images ideal for planetary observations, while reflectors excel in deep-sky viewing, revealing the nuances of nebulae and galaxy structures. The series typically offers apertures ranging from 6 to 10 inches, giving users the flexibility to select a model that best suits their observational needs.

Another feature that stands out in the LXD 75-Series is its user-friendly GoTo system. This system utilizes a database containing thousands of celestial objects and employs sophisticated software to navigate the night sky effortlessly. With a simple push of a button, users can locate and track objects, making the stargazing experience more engaging and less intimidating for beginners.

The LXD 75-Series also emphasizes durability and ease of assembly. The telescopes are designed for quick setup, with intuitive components that make it easy to get started in minutes. Additionally, the quality of craftsmanship ensures longevity, which is vital for a reliable observational tool.

In conclusion, the Meade LXD 75-Series stands out for its combination of advanced technologies and user-centric designs. With powerful tracking capabilities, versatile optical options, and an easy-to-use GoTo system, these telescopes cater to the diverse needs of astronomical enthusiasts. Whether for casual observation or serious astrophotography, the LXD 75-Series proves to be a stellar option for those looking to explore the wonders of the universe.
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