Meade LXD 75-Series instruction manual Aligning the Viewfinder, Choosing an Eyepiece

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Collimation Screws

Viewfinder

Eyepiece

Viewfinder

Bracket

Fig. 14a: Viewfinder assembly, refractor and Schmidt-Newtonian mod-

Collimation Screws

Viewfinder

 

Eyepiece

Viewfinder

Bracket

Fig. 14b: Viewfinder assembly, Newtonian models.

Important Note: Objects appear upside-down and reversed left-for-right when observed in the viewfinder. With refracting telescope models, objects viewed through the main telescope with the diagonal mirror in place are seen right-side-up, but reversed left-for-right.

This image inversion is of no consequence when observ- ing astronomical objects, and in fact all astronomical telescopes yield inverted images.

During terrestrial observing, where a fully-correctly-orient- ed image (right-side up and correct left-for-right) is desir- able, an optional Meade #928 45° Erect-Image Diagonal Prism is available. See OPTIONAL ACCES- SORIES, page 38.

Note that for Schmidt- Newtonian models, no means of image inversion is available; while these tele- scopes may be used for ter- restrial observing, the image will not be correctly oriented in either right-side-up or left- for-right orientations.

3.Achromatic refractor, Schmidt-Newtonian models and Newtonian models: Again, hold the optical tube so that it cannot accidentally swing freely. Lock the R.A. lock (33, Fig. 1d), and unlock the Dec. lock (17, Fig. 1d). The telescope now is able to move freely about the Dec. axis. Loosen the cradle ring lock knobs (13, Fig. 1a) so that the main tube slides easily back and forth in the cradle rings. Move the main tube in the cradle rings until the telescope remains in one posi- tion without tending to drift down in either direction. Re-lock the Dec. lock (17, Fig. 1d).

The telescope is now properly balanced on both axes. Next, the viewfinder must be aligned.

Aligning the Viewfinder

The wide field of view of the telescope's viewfinder (4, Fig. 1a) provides an easier way to initially sight objects than the main telescope's eyepiece (3, Fig. 1a), which has a much narrower field of view. If you have not already attached the viewfinder to the tel- escope tube assembly, follow the procedure described in step 9, page 12.

In order for the viewfinder to be useful, it must be aligned to the main telescope, so that both the viewfinder and telescope's optical tube (10, Fig. 1a) point at the same position in the sky. This alignment makes it easier to find objects: First locate an object in the wide-field viewfinder, then look into the eyepiece of the main telescope for a detailed view.

To align the viewfinder, perform steps 1 through 4 during the daytime; perform step 5 at night. Both the 6 x 30mm and the 8 x 50mm viewfinders align in an identical man- ner. Refer to Figs. 14a and 14b.

1.Remove the dust covers from the optical tube (9, Fig. 1a) and the viewfinder.

2.If you have not already done so, insert the low-power SP 26mm eyepiece (3, Fig. 1b) into the eyepiece holder of the main telescope. See step 10, page 12.

3.Look through the viewfinder eyepiece at an object at least one-half mile away (Tip: Remove the viewfinder tube from the bracket to simplify this operation). If the distant object is not in focus, turn the focus lock ring counterclockwise to loosen the viewfinder front cell (6, Fig. 1b). Twist the front cell until focus is achieved and retighten the focus lock ring.

4.Unlock the R.A. lock (33, Fig. 1d) and the Dec lock (17, Fig. 1d) so that the tel- escope turns freely on both axes. Then point the main telescope at a tall, well- defined and stationary land object (e.g., the top of a telephone pole) at least 200 yards distant and center the object in the telescope's eyepiece. Focus the image by turning the focus knobs (8, Fig. 1b). Retighten the R.A. and Dec. locks.

5.Look through the viewfinder and loosen or tighten, as appropriate, one or more of the viewfinder collimation thumbscrews (5, Fig. 1b) until the viewfinder’s crosshairs are precisely centered on the object you previously centered in the main telescope's eyepiece. You are now ready to make your first observations with your telescope.

NEVER point the telescope directly at or near the Sun at any time! Observing the Sun, even for the smallest fraction of a second, will result in instant and irreversible eye damage, as well as physical damage to the telescope itself.

5.Check this alignment on a celestial object, such as a bright star or the Moon, and make any necessary refinements, using the method outlined above in steps 3 and 4.

With this alignment performed, objects first located in the wide-field viewfinder will also appear in the telescope's eyepiece.

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.

Your telescope comes supplied with a Super Plössl (SP) 26mm eyepiece which gives a wide, comfortable field of view with high image resolution.

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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 Accessories How to Assemble Your TelescopeTelescope Assembly 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 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 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 SpecificationsMeade Customer Service Autostar SpecificationsAutostar Dimensions Inspecting the OpticsSetting Circles Appendix a Celestial CoordinatesOne-Star Polar Alignment Locating the Celestial PolePolar Alignment Two-Star Polar AlignmentEnhancement Methods Method #1 Three-Star Alignment Using AutostarPolar Alignment Viewfinder 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 TipsPEC Train Menu Option Method #4 Smart Drive Training Periodic Error CorrectionPEC Update Menu Option PEC Erase Menu OptionCity 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 LXD75 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 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.