Celestron 91525, 11055, 11065 instruction manual Celestial Observing

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Star hopping may take some getting used to since you can see more stars through the finder than you can see with the naked eye. And, some objects are not visible in the finder. One such object is M57, the famed Ring Nebula. Here’s how to find it:

1.Find the constellation of Lyra, a small parallelogram visible in the summer and fall months. Lyra is easy to pick out because it contains the bright star Vega.

2.Start at the star Vega — Alpha (α ) Lyrae — and move a few degrees southeast to find the parallelogram. The four stars that make up this geometric shape are all similar in brightness making them easy to see.

3.Locate the two southernmost stars that make up the parallelogram — Beta (β ) and Gamma (γ ) Lyrae.

4.Point the finder half way between these two stars.

5.Move about 1/2° toward Beta (β ) Lyrae, but remaining on a line that connects the two stars.

6.Look through the telescope and the Ring Nebula should be in the tele- scope. Its angular size is quite small and, therefore, not visible in the finder.

Because the Ring Nebula is rather faint, you may need to use averted vision to see it. Averted vision is the act of looking slightly away from the object you are observing. So, if you are observing the Ring Nebula, center it in the field of view and then look off toward the side. In this manner, light from the object is falling on the black and white sensitive rods as opposed to the color sensitive cones. These two examples should give you an idea of how to star hop to deep-sky objects. To use this method on other objects, consult any of the star atlases and star hop to the object of your choice using naked eye stars.

Figure 6-4

Although the Ring Nebula lies between two naked eye stars, it may take a little time to locate since it is not visible in the finder. Note that the scale for this star chart is different from the one on the previous page which shows several constella- tions including Pegasus, Triangulum, and Andromeda.

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Contents Page E C e l e s t r o n C M- 11 00/1400 B L E O F C O N T E N T S Iv Table of Contents T R O D U C T I O N How to Use This Manual Word of Caution Schmidt-Cassegrain Optical System Unpacking Your Celestron CM-1100 S E M B L I N G Y O U R C M 1 1 0CM-1100 Setting Up the Tripod Central Column Electronics Console Center Leg Brace Attaching the Center Leg Brace Attaching the Central ColumnAttaching the Equatorial Mount Installing Counterweight Installing Counterweight BarAttaching the Optical Tube to the Mount Attaching the Visual Back Installing the Star Diagonal Assembling Your CM-1100 Installing the Finder Installing the Polar Finder Moving the Telescope in R.A. and DEC Adjusting the Mount Balancing the Mount in R.A Balancing the Mount in DEC Assembling Your CM-1100 Technical Specifications Tripod Image Orientation L E S C O P E B a S I C SFocusing General Photography Hints Aligning the Finder Daytime Observing Your First LookNighttime Observing Calculating Magnification Determining Field of View Celestial Coordinate 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 Polar Axis Finder Declination Drift Aligning the R.A. Setting Circle Setting the DEC Circle I N G T H E D R I V E Powering Up the DriveGuide Speed BC Backlash Correction Periodic Error Correc- tionHC/CCD Hand Controller Northern/Southern Hemisphere OperationAutoguiding DEC ReverseObserving the Moon L E S T I a L O B S E R V I N G Observing the Sun Observing Deep-Sky Objects Using Your Setting CirclesStar Hopping Celestial Observing Seeing Conditions Viewing ConditionsTransparency Sky IlluminationCelestial Observing L E S T I a L P H O T O G R a P H Y Lunar Phase ISO Crescent Quarter Short Exposure Prime FocusFull Celestial Photography Piggyback Celestial Photography Eyepiece Projection Planet ISO Moon Mercury Venus Mars Jupiter Saturn Long Exposure Prime Focus Celestial Photography CCD Imaging Description of F-numbers Fastar ConfigurationImaging at f/7 Imaging at f/11 Medium size to small galaxiesLunar or small planetary nebulae Planetary or Lunar Imaging at f/22L E S C O P E M a I N T E N a N C E Care and Cleaning of the Optics CollimationTelescope Maintenance Telescope Maintenance T I O N a L a C C E S S O R I E S Optional Accessories Optional Accessories Optional Accessories Mag Type Proper Name ConstNGC# Spiral Galaxy Magnitude Epoch Star Name ConstellationVisual Observation Astronomy TextsAtlases General Observational AstronomyCelestron ONE Year Warranty