Celestron 31058, 31056 instruction manual Technical Specifications

Page 25

Technical Specifications

Below is pertinent technical information on your G-8N and C150-HD telescope that you may find useful.

	G-8N	C150-HD
Optical System:	Newtonian Reflector	Newtonian Reflector
Aperture:	200mm (8")	150mm (6")
Focal Length:	1000mm (40")	750mm (30")
Highest Useful Power:	480x	360x
Resolution (arc seconds):	0.58	.77
Light Gathering Power:	816	459
Limiting Visual Magnitude:	14	13.5
Secondary Obstruction	2.9"	2.2"
% of Primary Surface Area	13.1%	13.4%
f/ratio:	f/5	f/5
Length:	19.75"	14.5"
Weight
Optical Tube:	15.5 lb.	8.5 lb.
With Tripod:	30.5 lb.	25lb.

These specifications are approximate and subject to change without notice.

The G-8N • 25

Image 25

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 Transparency Viewing ConditionsSky Illumination SeeingCelestial 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