Meade LX200 instruction manual Magnification and Field of View toc 1. Magnifications

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IMPORTANT NOTICE! Never use a telescope or spotting scope to look at the Sun!
Observing the Sun, even for the shortest fraction of a
second, will cause irreversible damage to your eye as well as physical damage to the telescope or spotting scope itself.

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Meade LX200 Instruction Manuals

7" Maksutov-Cassegrain Telescope 8", 10", and 12" Schmidt-Cassegrain Telescopes

H. MAGNIFICATION AND FIELD OF VIEW [ toc ] 1. Magnifications

The magnification, or power, of the telescope depends on two optional characteristics: the focal length of the main telescope and the focal length of the eyepiece used during a particular observation. For example, the focal length of the LX200 7" f/15 is fixed at 2670mm, teh focal length of the LX200 8" f/10 telescope is fixed at 2000mm; the focal length of the 10" f/10 telescope is fixed at

2500mm; and the focal length of the 12" f/10 telescope is fixed at 3048mm. To calculate the power in use with a particular eyepiece, divide the focal length of the eyepiece into the focal length of the main telescope. For example, using the SP 26mm eyepiece supplied with the 8" f/10, the power is calculated as follows:

Power = 2000mm/26mm = 77X

The type of eyepiece (whether "MA" Modified Achromatic, "OR" Orthoscopic, "SP" Super Plössl, etc.) has no bearing on magnifying power but does affect such optical characteristics as field of view, flatness of field and color correction.

The maximum practical magnification is determined by the nature of the object being observed and, most importantly, by the prevailing atmospheric conditions. Under very steady atmospheric "seeing," the 7" LX200 may be used at powers up to about 450X on astronomical objects, the 8" LX200 may be used at powers up to about 500X, the 10" LX200 up to about 600X and the 12" up to about 750X. Generally, however, lower powers of perhaps 250X to 350X will be the maximum permissible, consistent with high image resolution. When unsteady air conditions prevail (as witnessed by rapid "twinkling" of the stars), extremely high-power eyepieces result in "empty magnification," where the object detail observed is actually diminished by the excessive power.

When beginning observations on a particular object, start with a low power eyepiece; get the object well- centered in the field of view and sharply focused. Then try the next step up in magnification. If the image starts to become fuzzy as you work into higher magnifications, then back down to a lower power–the atmospheric steadiness is not sufficient to support high powers at the time you are observing. Keep in mind that a bright, clearly resolved but smaller image will show far more detail than a dimmer, poorly resolved larger image.

Because of certain characteristics of the human eye (in particular, eye pupil diameter) and because of optical considerations inherent in the design of a telescope, there exists minimum practical power levels also. Generally speaking, the lowest usable power is approximately 4X per inch of telescope aperture, or about 28X in the case of the 7" telescope, 32X in the case of the 8" telescope, about 40X in the case of the 10" telescope and about 48X in the case of the 12" telescope. During the daytime, when human eye pupil

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Contents Meade Instruments Corporation LX200 Keypad Hand Controller Magnification and Field of View Related Topics Appendix B Equatorial UseImportant Note Introducing the Meade LX200Toc c. Altazimuth Mode Operation Toc 1. What Is the LX200? An OverviewToc e. Keypad and Power Panel Functions Toc a. Heavy-Duty Mounts with 9-speed Dual-Axis ElectronicsToc b Model LX200 Toc a Model LX200Toc c Model LX200 Toc d Model LX200Page We strongly recommend that you keep your original packing Unpacking and InspectionToc 1. What You Should Have Toc 2. Please Look Everything OverToc 4. Caution All LX200 Owners Keypad Version Number Toc 1. The Field Tripod 7, 8, 10 and 12 LX200 Models Telescope AssemblyPrecautionary Notes Page Toc 2. Mounting the Viewfinder 7, 8, 10, and 12 LX200 Models Toc c. Collimating the Viewfinder Toc b. Focusing the ViewfinderToc a. Attaching the Viewfinder Toc 6 Tube Swing-Through Limit Toc 4. Checking the Collimation of the OpticsToc 5 Tube Swing-Through Limit Toc 7. Maksutov Fan Quick Start Toc 1. Using the LX200 ManuallyToc 2. Using the LX200 In Land Toc a. Entering Basic Information Toc 3. Using the LX200 In Altazimuth AltazMotion Speeds Toc 1 Latitude and Longitude of the Observing Site Toc 2 Local Time and Date Toc b. Setting Up the Telescope Page Toc c. Using the Telescope Toc 1 The Mode Key Toc 3 Daytime Slewing Toc 2 Library Object KeysNext LX200 Keypad Hand Controller Toc 1. Enter Key Toc 2. Mode KeyToc 3. GO to Key Toc 4. Direction KeysToc 7. Focus Key Toc 6. RET KeyToc 8. MAP Key Toc 9. Object Keys M, STAR, and CngcPage Toc 1. ON/ OFF Switch LX200 Power PanelToc 4. DEC Motor Connector Toc 2. N/S SwitchToc 5. CCD Connector Toc 6. Power 12vDC ConnectorToc 9. Focuser Connector Toc 8. Reticle ConnectorToc 10. RS-232 Connector Toc 11. Aux ConnectorPage Toc 1. Mode One TELESCOPE/ Object Library Mode FunctionsToc a. Telescope Menu File Toc 1 SiteToc a Altaz Toc 2 AlignToc a -Star with Known Site Toc b -Star at Known SiteToc d. Which Alignment Method To Use? Toc c. Unknown SitePage Toc c Refined Polar Alignment Toc b PolarToc 3 Smart Toc e LandToc 5 Help Toc 4 12/24 HRToc 6 Reverse NS Toc 7 Reverse EWToc a LX200 Pointing Accuracy Toc 9 HP High-Precision PointingToc 11 DEC. Backlash Compensation Toc 2 Start Find Toc b. Object Library Menu FileToc 4 Parameters Toc 3 FieldToc a Type Gpdco Object Sysmbol LegendToc b Better Quality Symbol LegendToc c Higher Toc d LargerToc e Smaller Toc 2. Mode Two COORDINATES/ GO toToc f Brighter Toc g FainterToc c. Slew To Altaz Coordinates Toc 3. Mode Three CLOCK/ CalendarToc b. GO to Menu Option Toc b. FREQ= Menu File Toc 4. Mode Four TIMER/ Freq a. Timer = Menu OptionDrive Rate Settings Toc 5. Mode Five Keypad OFF/ Brightness Adjust Magnification and Field of View toc 1. Magnifications O.D., except as noted Toc 2. Apparent Field and Actual FieldPage Toc 1 Equatorial Wedge For 7 and 8 LX200 Appendix a Equatorial WedgeToc a. Azimuth Control Equatorial Wedge for 7 and 8 LX200 TelescopeToc b. Deluxe Latitude Adjuster Toc 2. Superwedge For 10 and 12LX200 Mounting Superwedge, b Latitude Range Holes Page Underside of the Drive Base Toc a. Setting Magnetic Declination Toc b. Compass Installation Toc c. Finding True North Page Page Next Page Toc 1. Celestial Coordinates Declination and Right Ascension Appendix B Equatorial USEPage Toc 2. Lining Up with the Celestial Pole Toc 3. Precise Polar Alignment Page Next Toc LX200 Alignment Star Library Appendix C LX200 Alignment Star Library and Star ChartsToc 1. Alignment Stars Star Charts for Northern Hemisphere Observers Page Next Page Toc 2. The Cngc Catalog Cngc Listings VQ GuideCngc Types Toc 3. The Star Catalog TagsToc 5. The M Catalog Toc 4. Select Star by NameToc 6. The Planets Object Library Planet Legend Toc 7. Other DatabasesConstellation Codes Related Topics Page Meade Instruments Corporation Page Toc 2. Collimation Alignment of the Optical System Page Defocused Star Images Toc 5. Factory Servicing and Repairs Toc 3. Adjusting the Right Ascension LockToc 4. Behind the Power Panel
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