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Meade 4504 APPENDIX A Calculating Eyepiece Power, Insert Barlow into focuser assembly

Models: 4504

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APPENDIX A: Calculating Eyepiece Power

APPENDIX A: Calculating Eyepiece Power

The power, or magnification of the telescope depends on two optical characteristics: the focal length of the main telescope and the focal length of the eyepiece used dur- ing a particular observation. The focal length of the 4504 telescope is fixed at 910mm. To calculate the power in use with a particular eyepiece, divide the focal length of the eyepiece into the focal length of the main telescope. E.g., using the H 25mm eyepiece supplied with the telescope, the power is calculated as follows:

Power =	telescope focal length	= 910mm	= 36x
	eyepiece focal length	25mm

The maximum practical magnification is determined by the nature of the object being observed and, most importantly, by the prevailing atmospheric conditions. Generally powers of perhaps 35x to 175x will be useful most often, consistent with high image resolution. When unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extreme high-power results in “empty magnification,” where the object detail observed is actually diminished by the excessive power.

The 3x Barlow lens included with your telescope triples the eyepiece magnification. To calculate the power of an eyepiece used with a Barlow lens, multiply the eyepiece power by the Barlow value. E.g., using the H 25mm eyepiece, the power or magnifi- cation of the 4504 telescope (as calculated in the example above) is 36x and the Barlow value is 3x. The total power using the Barlow lens is:

Total power = eyepiece power x Barlow value = 36 x 3 = 108x

To install the Barlow lens, first place the Barlow lens into the focuser assembly (remove the focuser dustcap, if necessary), followed by the eyepiece (Fig. 30). Tighten the Barlow thumbscrews and the focuser thumbscrews to a firm feel only.

Eyepiece

Thumbscrew

Barlow

	Focuser	Thumbscrew
	Assembly	Thumbscrew
	Assembly
		Focus knob

Fig. 30: Insert Barlow into focuser assembly.

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Meade 4504 instruction manual APPENDIX A Calculating Eyepiece Power, Insert Barlow into focuser assembly

Contents

Meade Instruments Corporation Meade Model 4.5 114mm Equatorial Reflecting TelescopeWith Starfinder Electronic Hand Controller MEADEHow This Manual is Organized PART TWO Starfinder Controls and Menus TABLE OF CONTENTSPART ONE The Basics PART THREE Caring for Your Telescopepage 1416Fig. 1 Parts included in the Meade Model 4504 Giftbox LESSON 1 Unpacking and Assembly PART ONE The BasicsKey to Figures 2a, 2b, and 2c Fig. 2a The Meade Model 4504 4.5 Equatorial Reflecting TelescopeFig. 2c The Meade Model 4504 4.5 Equatorial Reflecting Telescope 2325Fig. 2b The Meade Model 4504 4.5 Equatorial Reflecting Telescope pageHow to Assemble Your Telescope sure that this safety washer/knob always remains in place1. Threaded screw hole saddle plate 2. Saddle plate 3. Cradle ring Fig. 8 Insert eyepiece into the focuser assemblyFig. 7 Attach cradle rings to the saddle plate with attachment screws 4. Threaded screw hole cradle ring 5. Attachment screwLESSON 2 Balancing the Telescope LESSON 3 Aligning the ViewfinderLESSON 4 Observing by Moving the Telescope Manually Key to Figure Observe the World Around You LESSON 5 Observing Using Starfinders Arrow KeysMotor Drive System and Starfinder Handbox Installation Activate the Arrow Keys Slew SpeedsTo Polar Align the Telescope Observe the MoonLESSON 6 Tracking Objects Fig. 14 Latitude dial Fig. 15 Dec setting circleMoving Through Starfinder’s Menus Observe a Star using the Automatic Tracking FeatureLESSON 7 Using Starfinders GO TO Capabilities Initializing Starfinder Location Irvine Training the Drive Align Your Telescope Using Starfinder Check MountGo To Saturn Using the Guided TourWhich One’s the Alignment Star? Some Observation Tips Starfinder Controls PART TWO Starfinder Controls and Menusthe topmost screen Select Item Object Local Time and Local Sidereal Time LST Timer and Alarm StatusNOTE Pressing MODE while in the Select Item level moves Starfinder to Right Ascension and Declination coordinates8 Speed/? Key Briefly pressing the Speed/? key cycles through the seven slew speeds that move the telescope see “Slew Speeds,” page How Starfinders Menus Work Starfinder Navigation ExerciseTo Calculate Sunset time Starfinder Menus Object MenuEvent Menu Glossary MenuUtilities Menu Setup Menu Site provides access to the following options PART 3 Caring for Your Telescope CleaningMount and Tripod Adjustments Diagonal holder adjustments Fig. 23 Diagonal assemblySpider vane adjustments Collimation Alignment of the OpticsFig. 26 Spider vane misalignment Primary mirror adjustmentsFig. 25 Correct collimation Fig. 27 Diagonal mirror misalignmentStar testing the collimation STARFINDER DIMENSIONS MODEL 4504 TELESCOPE SPECIFICATIONSSTARFINDER SPECIFICATIONS DC servo motors with encoders, both axesAPPENDIX A Calculating Eyepiece Power Fig. 30 Insert Barlow into focuser assemblyPolar Alignment Terrestrial ViewingAstronomical Observing Understanding Celestial Movements and CoordinatesLining Up with the Celestial Pole Little Dipper Polaris Big Dipper CassiopeiaUsing Setting Circles Two-Star Polar AlignmentAPPENDIX C Using Starfinder to Enter Celestial Coordinates To GO TO a user-entered objectAPPENDIX D Helpful Charts Latitude Chart for Major Cities of the WorldObjects in Space APPENDIX E Basic AstronomyStarfinder Glossary The MoonFig. 36 The Pleiades is one of the most beautiful open clusters PlanetsDeep-Sky Objects A Roadmap to the Stars Star LocatorMeade Limited Warranty Meade Instruments Corporation A D V A N C E D P R O D U C T S D I V I S I O N