Celestron CGEM 1100 Instruction Manual page 3

Home Position ..................................................................................................................................................................................... 29
Light Control ....................................................................................................................................................................................... 29
Factory Settings................................................................................................................................................................................... 29
Version ................................................................................................................................................................................................ 29
Get Axis Position................................................................................................................................................................................. 29
Goto Axis Position .............................................................................................................................................................................. 29
Hibernate ............................................................................................................................................................................................. 29
Sun Menu ............................................................................................................................................................................................ 29
Scrolling Menu .................................................................................................................................................................................... 30
Set Mount Position .............................................................................................................................................................................. 30
Set Mount Position....................................................................................................................................................................................... 30
Turn On/Off GPS ................................................................................................................................................................................ 30
Turn On/Off RTC................................................................................................................................................................................ 30
Periodic Error Correction .................................................................................................................................................................... 30
TELESCOPE BASICS.............................................................................................................................................................................................................. 32
Image Orientation......................................................................................................................................................................................... 32
Focusing ....................................................................................................................................................................................................... 33
Calculating Magnification ............................................................................................................................................................................ 33
Determining Field of View........................................................................................................................................................................... 33
General Observing Hints .............................................................................................................................................................................. 34
ASTRONOMY BASICS ........................................................................................................................................................................................................... 35
The Celestial Coordinate System.................................................................................................................................................................. 35
Motion of the Stars ....................................................................................................................................................................................... 36
Polar Aligning the Mount ............................................................................................................................................................................. 37
Polar Align .......................................................................................................................................................................................... 37
Finding the North Celestial Pole................................................................................................................................................................... 39
CELESTIAL OBSERVING ..................................................................................................................................................................................................... 40
Observing the Moon ..................................................................................................................................................................................... 40
Lunar Observing Hints ................................................................................................................................................................................. 40
Observing the Planets ................................................................................................................................................................................... 40
Observing the Sun ........................................................................................................................................................................................ 40
Solar Observing Hints .................................................................................................................................................................................. 41
Observing Deep Sky Objects........................................................................................................................................................................ 41
Seeing Conditions......................................................................................................................................................................................... 41
Transparency ................................................................................................................................................................................................ 41
Sky Illumination ........................................................................................................................................................................................... 41
Seeing ........................................................................................................................................................................................................... 41
ASTROPHOTOGRAPHY........................................................................................................................................................................................................43
Short Exposure Prime Focus Photography ................................................................................................................................................... 43
Eyepiece Projection ...................................................................................................................................................................................... 44
Long Exposure Prime Focus Photography ................................................................................................................................................... 46
Periodic Error Correction (PEC) .................................................................................................................................................................. 47
Using Periodic Error Correction................................................................................................................................................................... 47
Terrestrial Photography ................................................................................................................................................................................ 48
Metering ....................................................................................................................................................................................................... 48
Reducing Vibration ...................................................................................................................................................................................... 48
CCD Imaging ............................................................................................................................................................................................... 49
Auto Guiding................................................................................................................................................................................................ 49
TELESCOPE MAINTENANCE.............................................................................................................................................................................................. 50
Care and Cleaning of the Optics ................................................................................................................................................................... 50
Collimation................................................................................................................................................................................................... 50
OPTIONAL ACCESSORIES .................................................................................................................................................................................................53
APPENDIX A - TECHNICAL SPECIFICATIONS............................................................................................................................................................ 56
APPENDIX B - GLOSSARY OF TERMS ............................................................................................................................................................................ 57
APPENDIX C - RS-232 CONNECTION ................................................................................................................................................................................60
APPENDIX D - TIME ZONE MAP........................................................................................................................................................................................ 62
SKY MAPS ................................................................................................................................................................................................................................64
3