Celestron CGE1400, CGE925, CGE1100, CGE800 manual Eyepiece Projection, Full

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•T-Max 400

•Any 100 to 400 ISO color slide film

•Fuji Super HG 400

•Ektar 25 or 100

2.Center the Moon in the field of your CGE telescope.

3.Focus the telescope by turning the focus knob until the image is sharp.

4.Set the shutter speed to the appropriate setting (see table below).

5.Trip the shutter using a cable release.

6.Advance the film and repeat the process.

Lunar Phase

ISO 50

ISO 100

ISO 200

ISO 400

Crescent

1/2

1/4

1/8

1/15

Quarter

1/15

1/30

1/60

1/125

Full

1/30

1/60

1/125

1/250

Table 7-1

Above is a listing of recommended exposure times when photographing the Moon at the

prime focus of your CGE telescope.

The exposure times listed in table 7-1 should be used as a starting point. Always make exposures that are longer and shorter than the recommended time. Also, take a few photos at each shutter speed. This will ensure that you will get a good photo.

•If using black and white film, try a yellow filter to reduce the light intensity and to increase contrast.

•Keep accurate records of your exposures. This information is useful if you want to repeat your results or if you want to submit some of your photos to various astronomy magazines for possible publication!

•This technique is also used for photographing the Sun with the proper solar filter.

Eyepiece Projection

This form of celestial photography is designed for objects with small angular sizes, primarily the Moon and planets. Planets, although physically quite large, appear small in angular size because of their great distances. Moderate to high magnification is, therefore, required to make the image large enough to see any detail. Unfortunately, the camera/telescope combination alone does not provide enough magnification to produce a usable image size on film. In order to get the image large enough, you must attach your camera to the telescope with the eyepiece in place. To do so, you need two additional accessories; a deluxe tele-extender (#93643), which attaches to the visual back, and a T-ring for your particular camera make (i.e., Minolta, Nikon, Pentax, etc.).

Because of the high magnifications during eyepiece projection, the field of view is quite small which makes it difficult to find and center objects. To make the job a little easier, align the finder as accurately as possible. This allows you to get the object in the telescope's field based on the finder's view alone.

Another problem introduced by the high magnification is vibration. Simply tripping the shutter  even with a cable release  produces enough vibration to smear the image. To get around this, use the camera's self-timer if the exposure time is less than one second  a common occurrence when photographing the Moon. For exposures over one second, use the "hat trick." This technique incorporates a hand-held black card placed over the aperture of the telescope to

Figure 7-1 - Accessories for

Projection Photography

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Contents CGE800 CGE925 CGE1100 CGE1400 User Defined Objects Telescope Maintenance Some of the many standard features of the CGE include 12v Output Jack CGE 1400 ShownDiagonal Setting up the TripodPower Supply CounterweightAttaching the Electronics Pier Attaching the Center Leg BraceAttaching the Equatorial Mount Installing the Counterweight BarInstalling the Counterweight Counterweight Locking Screw Safety Screw WasherAttaching the Visual Back Attaching the Optical Tube to the MountDovetail Slide Bar Dovetail Locking Knobs Mounting Platform Installing the Eyepiece Installing the Star DiagonalInstalling the Finderscope Moving the Telescope Manually Adjusting the MountBalancing The Mount in DEC Balancing The Mount in R.AAttaching the Motor Cables Powering the TelescopeTransporting the CGE Page CGE Hand Control Variable Stars Named StarsNamed Objects Double StarsStartup Procedure Alignment ProceduresAuto One-Star Align Auto Two-Star AlignLast Alignment Quick-AlignCGE Re-Alignment Finding Planets Object CatalogSelecting an Object Slewing to an ObjectRate Button Tour ModeConstellation Tour Direction ButtonsSetup Procedures Identify Precise GoTo Scope Setup FeaturesObserving Tip Helpful Hint Utility Features Helpful Hint Page CGE Ready Image Orientation Calculating Magnification FocusingDetermining Field of View General Observing Hints Celestial Coordinate System Motion of the Stars Pointing at Polaris Latitude ScalesFinding the North Celestial Pole Declination Drift Method of Polar Alignment Planetary Observing Hints Observing the MoonLunar Observing Hints Observing the PlanetsSeeing Conditions Observing the SunSolar Observing Hints Observing Deep Sky ObjectsSeeing Short Exposure Prime Focus Photography Full Eyepiece ProjectionPlanet ISO Moon Mercury Venus Mars Jupiter Saturn Long Exposure Prime Focus PhotographyPeriodic Error Correction PEC Using Periodic Error Correction CCD Imaging Terrestrial PhotographyMetering Reducing VibrationFastar Compatible Optical System Fastar F/2 Imaging Medium size to small galaxies With Reducer/CorrectorPlanetary or Lunar Auto Guiding Collimation Care and Cleaning of the OpticsCollimated telescope Should appear Symmetrical with Page At f/10 and 163 power with the CGE Page Technical Specifications Idle Current Appendix a Longitudes Latitudes Georgia Minnesota Rhode Island Canada Communication Protocol Appendix B RS-232 ConnectionReset The Position Of Azm Or Alt Additional RS232 CommandsAppendix C Maps of Time Zones Page Page Page Page Page Page Page Celestron TWO Year Warranty
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