Manuals / Celestron / Lawn and Garden / Telescope

Celestron CGE925, CGE1100, CGE800 Secondary Mirror Secondary Mirror Retaining Ring Corrector Plate

Models: CGE1400 CGE800 CGE1100 CGE925

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Secondary

Secondary

Mirror

Secondary

Mirror

Retaining Ring

Corrector Plate

Secondary

Mirror Mount

Handle

Figure 7-2 - The Fastar Compatible Optical System

compatible CGE telescope's versatility allows it to be used in many different f-number configurations for CCD imaging. It can be used at f/2 (with optional Fastar Lens Assembly), f/6.3 (with the optional Reducer/Corrector), f/10, and f/20 (with the optional 2x Barlow) making it the most versatile imaging system available today. This makes the system ideal for imaging deep-sky objects as well as planetary detail. Described below is the configuration of each F-number and the type of object best suited to that kind of imaging.

The above figure shows how the secondary mirror is removed when using the optional CCD camera at f/2 and the Fastar Lens Assembly.

Warning: The secondary mirror should never be removed unless installing the optional Fastar Lens Assembly. Adjustments to collimation can easily be made by turning the screws on the top of the secondary mirror mount without ever having to remove the secondary mirror (see Telescope Maintenance section of this manual).

The F/# stands for the ratio between the focal length and the diameter of the light gathering element. A CGE1100 optical tube has a focal length of 110 inches and a diameter of 11 inches. This makes the system an f/10, (focal length divided by diameter). The CGE 800 has a focal length of 80 inches and a diameter of 8 inches, also making it an f/10 optical system. However, the CGE 1400 optical tube has a 154 inch focal length with a F-ratio of f/11. When the secondary is removed and the CCD camera is placed at the Fastar position, the system becomes f/2, this is a unique feature to some Celestron telescopes (see figures below).

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Celestron CGE925, CGE1100, CGE800, CGE1400 manual Secondary Mirror Secondary Mirror Retaining Ring Corrector Plate

Contents

CGE800 CGE925 CGE1100 CGE1400 INSTRUCTION MANUALPeriodic Error Correction ASSEMBLYUser Defined Objects INTRODUCTIONASTRONOMY BASICS Some of the many standard features of the CGE include Counterweights Latitude Adjustment ScaleCounterweight Bar On/Off SwitchSetting up the Tripod Power SupplyCounterweight CGE 800 #11058Attaching the Center Leg Brace Attaching the Electronics PierElectronincs Pier Tripod LegInstalling the Counterweight Bar Installing the CounterweightDec Axis Counterweight Bar Counterweight Locking Screw Safety Screw and WasherAttaching the Optical Tube to the Mount Attaching the Visual BackDovetail Slide Bar Dovetail Locking Knobs Mounting Platform Installing the Star Diagonal Installing the EyepieceInstalling the Finderscope Adjusting the Mount Moving the Telescope ManuallyBalancing The Mount in R.A Balancing The Mount in DECGO OF THE TELESCOPE TUBE COMPLETELY Powering the Telescope Attaching the Motor CablesTransporting the CGE 6. Remove the center leg brace from the tripod 7. Collapse the tripod legs inward, towards each otherThe CGE Hand Control Named Stars Named ObjectsDouble Stars Variable StarsAlignment Procedures Startup ProcedureCalibrating the CGE Mount stars using the up arrow button and the right arrow button Approaching the star from this direction when looking through theAuto Two-Star Align Auto One-Star AlignQuick-Align Last AlignmentCGE Re-Alignment Object Catalog Selecting an ObjectSlewing to an Object Finding PlanetsTour Mode Constellation TourDirection Buttons Rate ButtonSetup Procedures 1 = 2 = 1x sidereal 3 = 4 = 5 =6 = 7 = .5º / sec 8 = 2º / sec 9 = 4º / sec Identify Helpful HintScope Setup Features Precise GoToObserving Tip Helpful Hint Utility Features MOVE TO SWITCHLIGHT CONTROL FACTORY SETTING UTILITIES CALIBRATE MOUNTHelpful Hint Page command functions CGE ReadyCGE Menu Tree MENUImage Orientation Actual image orientation as seen with the unaided eyeReversed from left to right, as viewed with a Star Diagonal Focusing Calculating MagnificationDetermining Field of View General Observing Hints The Celestial Coordinate System The celestial sphere seen from the outside showing R.A. and DECMotion of the Stars Latitude Scales Pointing at PolarisFinding the North Celestial Pole the south celestial poleDeclination Drift Method of Polar Alignment Observing the Moon Lunar Observing HintsObserving the Planets Planetary Observing HintsObserving the Sun Solar Observing HintsObserving Deep Sky Objects Seeing ConditionsSeeing Short Exposure Prime Focus Photography Eyepiece Projection Lunar PhaseCrescent QuarterLong Exposure Prime Focus Photography PlanetMoon MercuryPeriodic Error Correction PEC Using Periodic Error Correction Terrestrial Photography MeteringReducing Vibration CCD ImagingSecondary Mirror Secondary Mirror Retaining Ring Corrector Plate Lens Accessory TelescopeStandard WithF/6.3 with Reducer/Corrector Medium size to small galaxiesPlanetary or Lunar Figure 7-5 M27 -- The DumbbellAuto Guiding Care and Cleaning of the Optics CollimationTo make collimation a simple procedure, follow these easy steps 40mm 11 at f/10 and 163 power with the CGE exposure lunar and filtered solar photography Technical Specifications EQ Mount WeightCounter Weight bar Counter WeightTechnical Specifications Slew SpeedsIdle Current Slew one axisAPPENDIX A LONGITUDES AND LATITUDES CONNECTICUTLONGITUDE LONGITUDE LONGITUDE CANADA INTERNATIONALAppendix B - RS-232 Connection Communication ProtocolPC Command ASCII Commands belowAdditional RS232 Commands Reset The Position Of Azm Or AltSend Any Track Rate Through RS232 To The Hand Control APPENDIX C - MAPS OF TIME ZONES Page Page Page Page Page Page Page CELESTRON TWO YEAR WARRANTY Celestron 2835 Columbia Street Torrance, CA Tel. 310 Fax. 310 Copyright 2003 Celestron All rights reservedProducts or instructions may change without notice or obligation Item # 11063-INST $10.00