INSTRUCTION MANUAL NexStar 90 MAK . NexStar 127 MAK .
TABLE OF CONTENTS INTRODUCTION ............................................................................................................................................................ 4 Warning .......................................................................................................................................................................... 4 ASSEMBLY ...................................................................................................................................
Scrolling Menu ......................................................................................................................................................... 23 Calibrate Goto........................................................................................................................................................... 23 Set Mount Position....................................................................................................................................................
Congratulations on your purchase of the Celestron NexStar telescope! The NexStar ushers in a whole new generation of computer automated technology. Simple and friendly to use, the NexStar is up and running after locating just three bright celestial objects. It’s the perfect combination of power and portability.
11 12 1 10 2 9 3 4 5 6 8 7 = The NexStar SLT Telescope (NexStar 127MAK Shown) 1 2 3 4 5 6 Corrector Lens Fork Arm Battery Compartment Tripod Coupling Screw Tripod Accessory Tray 7 8 9 10 11 12 5 Tripod Leg Extension Clamp Hand Control Star Diagonal Eyepiece Star Pointer Finderscope Telescope Tube
The NexStar comes partially assembled and can be operational in a matter of minutes.
Attaching the Hand Control Holder The NexStar comes with a snap-on hand control holder that conveniently attaches to any of the tripod legs. To attach the hand control holder simply position the holder with the square plastic tab facing up and push against the tripod leg until it snaps in to place.
The Eyepiece The eyepiece, is the optical element that magnifies the image focused by the telescope. The eyepiece fits directly into the star diagonal. To install the eyepiece: 1. Loosen the thumbscrew on the star diagonal so it does not obstruct the inner diameter of the eyepiece end of the diagonal. Remove the protective dust cap from the star diagonal's barrel. 2. Slide the chrome portion of the low power 25mm eyepiece into the star diagonal. 3. Tighten the thumbscrew to hold the eyepiece in place.
Sight Tube ON/OFF Brightness Control Azimuth Adjustment Control Battery Compartment (not shown) Dovetail Tightening Screw Altitude Adjustment Control Dovetail Mount Figure 2-8 The Star Pointer Finderscope with Bracket Star Pointer Installation 1. Slide the Star Pointer bracket into the dovetail mounting platform on top of the focuser assembly (see figure 2-9). 2. Orient the Star Pointer so that the sight tube is facing towards the front of the tube. 3.
If the LED dot is brighter than the alignment star, it may make it difficult to see the star. Turn the brightness control counterclockwise, until the red dot is the same brightness as the alignment star. This will make it easier to get an accurate alignment. The Star Pointer is now ready to be used.
The Hand Control The NexStar SLT's hand controller is designed to give you instant access to all the functions the NexStar has to offer. With automatic slewing to over 4,000 objects, and common sense menu descriptions, even a beginner can master its variety of features in just a few observing sessions. Below is a brief description of the individual components of the NexStar SLT hand controller: 1. 2. 3. 4.
1 7 2 8 3 9 10 4 5 11 6 12 Figu ure 3-1 The NexStar Hand Control 5. 6. Info: Displays coordinates and useful information about objects selected from the NexStar database. Tour: Activates the tour mode, which seeks out all the best objects for a given month and automatically slews the NexStar to those objects. 7. Enter: Pressing Enter allows you to select any of the NexStar functions, accept entered parameters and slew the telescope to displayed objects. 8.
Alignment Procedure In order for the NexStar to accurately point to objects in the sky, it must first be aligned to known positions (stars) in the sky. With this information, the telescope can create a model of the sky, which it uses to locate any object with known coordinates. There are many ways to align the NexStar with the sky depending on what information the user is able to provide: SkyAlign uses your current date, time and city to create an accurate model of the sky.
Time - Helpful Hints Enter the current time for your area. You can enter either the local time (i.e. 8:00), or you can enter military time (i.e. 20:00). Select PM or AM. If military time was entered, the hand control will bypass this step. Choose between Standard time or Daylight Savings time. Use the Up and Down scroll buttons (10) to toggle between options. Select the time zone that you are observing from. Again, use the Up and Down buttons (10) to scroll through the choices.
Auto Two-Star Align As with Sky Align, Auto Two-Star Align requires you to enter all the necessary time/site information as before. Once this information is entered, NexStar will prompt you to select and point the telescope at one known star in the sky. The NexStar now has all the information it needs to automatically choose a second star that will assure the best possible alignment. Once selected the telescope will automatically slew to that second alignment star to complete the alignment.
One-Star Align One-Star Align requires you to input all the same information as you would for the Two-Star Align procedure. However, instead of slewing to two alignment stars for centering and alignment, the NexStar uses only one star to model the sky based on the information given. This will allow you to roughly slew to the coordinates of bright objects like the moon and planets and gives the NexStar the information needed to track objects in altazimuth in any part of the sky.
NexStar Re-Alignment The NexStar has a re-alignment feature which allows you to replace either of the original alignment stars with a new star or celestial object. This can be useful in several situations: If you are observing over a period of a few hours, you may notice that your original two alignment stars have drifted towards the west considerably. (Remember that the stars are moving at a rate of 15º every hour).
Slewing to an Object Once the desired object is displayed on the hand control screen, you have two options: Press the INFO Key. This will give you useful information about the selected object such as magnitude, constellation and fascinating facts about many of the objects. Press the ENTER Key. This will automatically slew the telescope to the coordinates of the object.
Direction Buttons The NexStar has four direction buttons in the center of the hand control which controls the telescope motion in altitude (up and down) and azimuth (left and right). The telescope can be controlled at nine different speed rates.
Tracking Rate - In addition to being able to move the telescope with the hand control buttons, the NexStar will continually track a celestial object as it moves across the night sky. The tracking rate can be changed depending on what type of object is being observed: Sidereal Lunar Solar This rate compensates for the rotation of the earth by moving the telescope at the same rate as the rotation of the earth, but in the opposite direction.
Identify Identify Mode will search any of the NexStar database catalogs or lists and display the name and offset distances to the nearest matching objects. This feature can serve two purposes. First, it can be used to identify an unknown object in the field of view of your eyepiece. Additionally, Identify Mode can be used to find other celestial objects that are close to the objects you are currently observing.
control, press the MENU button and select Direction Buttons from the Utilities menu. Use the Up/Down arrow keys (10) to select either the Azimuth buttons (left and right) or Altitude buttons (up and down) and press ENTER. Pressing ENTER again will reverse the direction of the hand control buttons from their current state. Direction Buttons will only change the eyepiece rates (rate 1-6) and will not affect the slew rates (rate 7-9).
Sun Menu For safety purposes the Sun will not be displayed as a database object unless it is first enabled. The enable the Sun, go to the Sun Menu and press ENTER. The Sun will now be displayed in the Planets catalog as can be used as an alignment object when using the Solar System Alignment method. To remove the Sun from displaying on the hand control, once again select the Sun Menu from the Utilities Menu and press ENTER.
NexStar SLT MENU TRACKING MODE ALT-AZ EQ NORTH EQ SOUTH OFF RATE SIDEREAL SOLAR LUNAR VIEW TIME-SITE SCOPE SETUP SETUP TIME-SITE ANTI-BACKLASH SLEW LIMITS FILTER LIMITS DIRECTION BUTTONS GOTO APPROACH CORDWRAP UTILITIES GPS ON/OFF LIGHT CONTROL FACTORY SETTING VERSION GET ALT-AZ GOTO ALT-AZ HIBERNATE SUN MENU SCROLLING MENU USER OBJECTS GOTO SKY OBJ SAVE SKY OBJ SAVE DB OBJ ENTER RA & DEC SAVE LAND OBJ GOTO LAND OBJ GET RA-DEC GOTO RA-DEC INDENTIFY SELECT CATALOG ALIGNMENT LIST SKY ALIGN Saved Site ENTER
A telescope is an instrument that collects and focuses light. The nature of the optical design determines how the light is focused. Some telescopes, known as refractors, use lenses. Other telescopes, known as reflectors, use mirrors. The Maksutov-Cassegrain optical system uses a combination of mirrors and lenses and is referred to as a compound or catadioptric telescope. This unique design offers large-diameter optics while maintaining very short tube lengths, making them extremely portable.
Calculating Magnification You can change the power of your telescope just by changing the eyepiece (ocular). To determine the magnification of your telescope, simply divide the focal length of the telescope by the focal length of the eyepiece used. In equation format, the formula looks like this: Focal Length of Telescope (mm) Magnification = Focal Length of Eyepiece (mm) Let’s say, for example, you are using the 25mm eyepiece.
With your telescope set up, you are ready to use it for observing. This section covers visual observing hints for both solar system and deep sky objects as well as general observing conditions which will affect your ability to observe. Observing the Moon Often, it is tempting to look at the Moon when it is full. At this time, the face we see is fully illuminated and its light can be overpowering. In addition, little or no contrast can be seen during this phase.
Solar Observing Hints The best time to observe the Sun is in the early morning or late afternoon when the air is cooler. To center the Sun without looking into the eyepiece, watch the shadow of the telescope tube until it forms a circular shadow. To ensure accurate tracking on SLT models, be sure to select solar tracking rate. Observing Deep Sky Objects Deep sky objects are simply those objects outside the boundaries of our solar system.
Seeing Seeing conditions refers to the stability of the atmosphere and directly affects the amount of fine detail seen in extended objects. The air in our atmosphere acts as a lens which bends and distorts incoming light rays. The amount of bending depends on air density. Varying temperature layers have different densities and, therefore, bend light differently. Light rays from the same object arrive slightly displaced creating an imperfect or smeared image.
While your NexStar telescope requires little maintenance, there are a few things to remember that will ensure your telescope performs at its best. Care and Cleaning of the Optics Occasionally, dust and/or moisture may build up on the lens of your telescope. Special care should be taken when cleaning any instrument so as not to damage the optics. If dust has built up on the optics, remove it with a brush (made of camel’s hair) or a can of pressurized air.
To collimate your telescope, remove the diagonal and eyepiece and look into rear opening of the tube (also remove the dust cover from the front of the tube). This can be done indoors, with the telescope pointed at a white wall in a well-lit room. Try to keep your eye centered with respect to the rear opening of the tube as best as possible. Using a Collimating Eyepiece will aid greatly in keeping your eye centered and is strongly recommend (see Accessories section).
You will find that additional accessories enhance your viewing pleasure and expand the usefulness of your telescope. For ease of reference, all the accessories are listed in alphabetical order. Adapter, Car Battery (#18778) – Celestron offers the Car Battery Adapter that allows you to run the NexStar drive off an external power source. The adapter attaches to the cigarette lighter of your car, truck, van, or motorcycle. Barlow lens, OMNI 1.
UHC/LPR Filter #94123 Filter, Light Pollution Reduction – UHC/LPR (#94123) – These filters are designed to enhance your views of deep sky astronomical objects when viewed from urban areas. LPR Filters selectively reduce the transmission of certain wavelength of light, specifically those produced by artificial lights. This includes mercury and high and low pressure sodium vapor lights. In addition, they also block unwanted natural light (sky glow) caused by neutral oxygen emission in our atmosphere.
APPENDIX A - TECHNICAL SPECIFICATIONS O O p S p o n Op ptttiiicccaaalll S Sp peeeccciiifffiiicccaaatttiiio on n Design Aperture Focal Length F/ratio of the Optical System Optical Coatings Highest Useful Magnification Resolution: Rayleigh Criterion Dawes Limit Light Gathering Power Field of View: Standard Eyepiece Linear Field of View (at 1000 yds) Eyepiece Magnification: Optical Tube Length NexStar 90mm Maksutov-Cassegrain 90mm 1250mm 14 Fully Coated 213x 1.55 arc seconds 1.
GLOSSARY OF TERMS AAbsolute magnitude Airy disk Alt-Azimuth Mounting Altitude Aperture Apparent Magnitude Arc minute Arc second Asterism Asteroid Astrology Astronomical unit (AU) Aurora Azimuth BBinary Stars CCelestial Equator Celestial pole Celestial Sphere Collimation DDeclination (DEC) EEcliptic Equatorial mount FFocal length G GoTo The apparent magnitude that a star would have if it were observed from a standard distance of 10 parsecs, or 32.6 light-years. The absolute magnitude of the Sun is 4.8.
JJovian Planets KKuiper Belt LLight-Year (ly) MMagnitude Meridian Messier NNebula North Celestial Pole Nova OOpen Cluster PParallax Parfocal Parsec Point Source RReflector Resolution Right Ascension: (RA) SSidereal Rate Any of the four gas giant planets that are at a greater distance form the sun than the terrestrial planets. A region beyond the orbit of Neptune extending to about 1000 AU which is a source of many short period comets.
TTerminator UUniverse VVariable Star WWaning Moon The boundary line between the light and dark portion of the moon or a planet. The totality of astronomical things, events, relations and energies capable of being described objectively. A star whose brightness varies over time due to either inherent properties of the star or something eclipsing or obscuring the brightness of the star. The period of the moon's cycle between full and new, when its illuminated portion is decreasing.
Appendix C - RS-232 Connection Using the included NSOL software you can control your NexStar telescope with a computer via the RS-232 port located on the computerized hand control and using the RS-232 cable (#93920). For information about using NSOL to control your telescope, refer to the instruction sheet that came with the CD and the help files located on the disk. In addition to NSOL, the telescope can be controlled using other popular astronomy software programs.
APPENDIX D – MAPS OF TIME ZONES 39
Celestron 2835 Columbia Street Torrance, CA 90503 Tel. (310) 328-9560 Fax. (310) 212-5835 Web site at http://www.celestron.com Copyright 2010 Celestron All rights reserved. (Products or instructions may change without notice or obligation.) This device complies with Part 15 of the FCC Rule.