Celestron NexStar GPS 93507 Instruction Manual page 3

Version ................................................................................................................................................................26
Get Alt-Az ...........................................................................................................................................................26
Goto Alt-Az.........................................................................................................................................................26
TELESCOPE BASICS..................................................................................................................................................28
Image Orientation ...................................................................................................................................................28
Focusing..................................................................................................................................................................29
Calculating Magnification.......................................................................................................................................29
Determining Field of View ......................................................................................................................................29
General Observing Hints.........................................................................................................................................30
ASTRONOMY BASICS ...............................................................................................................................................31
The Celestial Coordinate System.............................................................................................................................31
Motion of the Stars ..................................................................................................................................................32
Polar Alignment (with optional Wedge) ..................................................................................................................33
Wedge Align .......................................................................................................................................................33
Finding the North Celestial Pole.............................................................................................................................33
Declination Drift Method of Polar Alignment.....................................................................................................34
CELESTIAL OBSERVING .........................................................................................................................................36
Observing the Moon ................................................................................................................................................36
Lunar Observing Hints ........................................................................................................................................36
Observing the Planets .............................................................................................................................................36
Planetary Observing Hints...................................................................................................................................36
Observing the Sun ...................................................................................................................................................37
Solar Observing Hints .........................................................................................................................................37
Observing Deep Sky Objects ...................................................................................................................................37
Seeing Conditions....................................................................................................................................................37
Transparency...........................................................................................................................................................37
Sky Illumination.......................................................................................................................................................37
Seeing ......................................................................................................................................................................38
CELESTIAL PHOTOGRAPHY..................................................................................................................................39
Short Exposure Prime Focus Photography .............................................................................................................39
Eyepiece Projection.................................................................................................................................................40
Long Exposure Prime Focus Photography..............................................................................................................41
Periodic Error Correction (PEC)............................................................................................................................42
Using Periodic Error Correction..........................................................................................................................42
Terrestrial Photography..........................................................................................................................................43
Metering ..............................................................................................................................................................44
Reducing Vibration .............................................................................................................................................44
CCD Imaging ..........................................................................................................................................................44
Fastar F/2 Imaging..............................................................................................................................................46
F/6.3 with Reducer/Corrector ..............................................................................................................................46
Auto Guiding.......................................................................................................................................................47
TELESCOPE MAINTENANCE..................................................................................................................................48
Care and Cleaning of the Optics .............................................................................................................................48
Collimation..............................................................................................................................................................48
OPTIONAL ACCESSORIES .....................................................................................................................................50
APPENDIX A - TECHNICAL SPECIFICATIONS ..................................................................................................53
APPENDIX B - GLOSSARY OF TERMS..................................................................................................................54
APPENDIX C - LONGITUDES AND LATITUDES.................................................................................................57
APPENDIX D - RS-232 CONNECTION....................................................................................................................62
Communication Protocol:....................................................................................................................................62
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