Celestron NexStar 8i manual

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The amount of bending depends on air density. Varying temperature layers have different densities and, therefore, bend light differently. Light rays from the same object arrive slightly displaced creating an imperfect or smeared image. These atmospheric disturbances vary from time-to-time and place-to-place. The size of the air parcels compared to your aperture determines the "seeing" quality. Under good seeing conditions, fine detail is visible on the brighter planets like Jupiter and Mars, and stars are pinpoint images. Under poor seeing conditions, images are blurred and stars appear as blobs.

The conditions described here apply to both visual and photographic observations.

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Contents Page Hand Control Operation Alignment Procedures Care and Cleaning of the Optics Collimation Page NexStar 8i SE StarPointer Finderscope Eyepiece Diagonal Visual Back Appendix C Longitude Latitude Mounting the Telescope to the Tripod Assembling the NexStarPowering the NexStar Hand ControlStar Diagonal Star Pointer Installation EyepieceStar Pointer Finderscope Star Pointer Operation NexStar Computerized Hand Control Double Stars Hand Control OperationAuto Two-Star Align Alignment ProceduresTwo Star Alignment EQ North / EQ South Alignment Object CatalogNexStar Re-Alignment Selecting an ObjectTour Mode Finding PlanetsSlewing to an Object Setup Procedures Direction ButtonsRate Button Page Menu Scope Setup FeaturesUtility Features Helpful Hint NexStar Ready Image Orientation Focusing Calculating MagnificationDetermining Field of View General Observing Hints Celestial Coordinate System Motion of the Stars Wedge Align Polar Alignment with optional WedgeFinding the North Celestial Pole Observing the Planets Observing the MoonObserving the Sun Lunar Observing HintsSeeing Conditions Observing Deep Sky ObjectsTransparency Sky IlluminationPage Short Exposure Prime Focus Photography Full Eyepiece ProjectionPlanet ISO Moon Mercury Venus Mars Jupiter Saturn Long Exposure Prime Focus PhotographyPage CCD Imaging Terrestrial PhotographyMetering Reducing VibrationCollimation Care and Cleaning of the OpticsCollimated telescope Should appear Symmetrical with Page Adapter, Car Battery #18769 Page Page Appendix a Technical Specifications Page Appendix B Glossary of Terms Trillion km 5.87 X 1 trillion mi Right Ascension RA Appendix C Longitudes Latitudes Georgia Minnesota Rhode Island Canada Communication Protocol Appendix D RS-232 ConnectionAppendix E Maps of Time Zones Page Page Page Page Page Page Page Celestron TWO Year Warranty