Celestron 31058, 31056 instruction manual L E S T I a L P H O T O G R a P H Y

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C E L E S T I A L P H O T O G R A P H Y

After looking at the night sky for awhile you may want to try photographing it. Several forms of celestial photography are possible with your Celestron telescope. The most common forms of celestial photography, in order of difficulty are: short exposure prime focus, piggyback, eyepiece projection, and long exposure deep sky. Each of these is discussed in moderate detail with enough information to get you started. Topics include the accessories required and some simple techniques. More information is available in some of the publications listed at the end of this manual.

In addition to the specific accessories required for each type of celestial photography, there is the need for a camera — but not just any camera. The camera does not have to have many of the features offered on today’s state-of- the-art equipment. For example, you don’t need auto focus capability or mirror lock up. Here are the mandatory features a camera needs for celestial photog- raphy. First, a ‘B’ setting which allows for time exposures. This excludes point and shoot cameras and limits the selection to 35mm SLR cameras.

Second, the ‘B’ or manual setting should not run off the battery. Many new electronic cameras use the battery to keep the shutter open during time exposures. Once the batteries are drained, usually after a few minutes, the shutter closes, whether you have finished with the exposure or not. Look for a camera that has a manual shutter when operating in the time exposure mode. Olympus, Nikon, Minolta, Pentax, Canon and others have made such camera bodies.

The camera should have interchangeable lenses so you can attach it to the telescope and use a variety of lenses for piggyback photography. If you can’t find a new camera, you can purchase a used camera body that is not 100- percent functional. The light meter does not have to be operational since you will be determining the exposure length manually.

Use a cable release with a locking function to hold the shutter open while you do other things. Mechanical and air releases are available at most camera stores.

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Contents C150-HD and G-8N Newtonian Page B L E N T E N T S Celestial Photography T R O D U C T I O N How to Use this Manual Word of Caution Newtonian Optical System Unpacking Your G-8N S E M B L I N G Y O U R N E W T O N I a N T E L E S C O P EG-8N C150-HD Adjusting the Tripod Height Setting Up the TripodAttaching the Accessory Tray They are needed later for polar alignment Attaching the Equatorial MountAttaching the R.A. Slow Motion Knob Attaching the Declination Slow Motion Knob Attaching the Counterweight Bar and Counterweight Attaching the Telescope to the Mount For G-8N Attaching the Telescope to the Mount For C150- HD Balancing the Telescope in R.A Removing the Lens CapCompletely Balancing the Telescope in DECG-8N C150-HD Installing the Finderscope Installing the Eye- piece Technical Specifications ActualVeiw NewtonianView Image OrientationFocusing Aligning the Finder Daytime Observing Your First LookNighttime Observing Calculating Magnification Determining Field of View Celestial Coordi- nate System T R O N O M Y B a S I C SMotion of the Stars Definition Polar AlignmentFinding the Pole Latitude Scales Pointing at Polaris Declination Drift Polar Alignment Finders Aligning the R.A Setting CircleObserving the Moon Planets L E S T I a L O B S E R V I N GObserving Deep-Sky Objects Observing the S u nUsing the Setting Circles Star Hopping Celestial Observing Seeing Viewing ConditionsTransparency Sky IlluminationCelestial Observing L E S T I a L P H O T O G R a P H Y Short Exposure Prime F o c u s Lunar Phase ISO Crescent Quarter 125 Full 250Piggyback Celestial Photography L E S C O P E M a I N T E N a N C E Care and Cleaning of the Optics CollimationOr back out the holder screws more than one 1 to two 2 turns T I O N a L a C C E S S O R I E S Optional Accessories Single Axis Motor Drive System #93518 Themessiercatalog Great Orion Nebula Elliptical Galaxy List of Bright Stars For Further Reading Celestron ONE Year Warranty