Argo NavisTM

 

User Manual

 

 

   Edition 11, Dec 2014, for Argo NavisTM Model 102 & 102B,

Firmware version 3.0.0

 


Congratulations

 


You have purchased one of the most sophisticated devices for rapidly and confidently locating celestial objects. The Argo NavisTM Digital Telescope Computer (DTC) brings not only accurate positioning information to your telescope but also provides an enormous detailed database of tens of thousands of objects.

Stars, galaxies, galaxy clusters, globular clusters, open clusters, planetary nebulae, nebulae, planets, asteroids, comets, earth-orbiting satellites and more.

Magnitudes, surface brightness, object sizes, common names, stellar classifications, stellar luminosity classes, double star separations, variable star periods, Hubble galaxy morphologies, constellation, detailed parameters of planets, comets, asteroids, satellites, Moon phases and a wealth of other information are available at your fingertips with a simple spin of the dial.

A large range of mounts can accommodate the Argo NavisTM including Dobsonians, Forks, German Equatorials and Equatorial Tables.

 Handheld and powered by AA batteries, or an optional external DC source, Argo NavisTM operates completely standalone.

After fitting a pair of optical encoders to your mount, using the Argo NavisTM is simple. Perform a quick star alignment and off you go. There is no need to level or accurately polar align your mount. It's fast and easy.

Using the innovative, Intelligent Editing SystemTM, objects from the in-built catalogs can be accessed quickly and easily by name. You can select a particular object and then Argo NavisTM can provide you with “guiding” information that will allow you to zero-in on it by simply manually turning the scope.

Alternatively, objects of interest can be reported to you on the display in real-time as you move your scope. Argo NavisTM has a powerful 32-bit CPU at its heart that will easily allow you to continuously track satellites. The sophisticated software even accounts for precession, nutation and atmospheric refraction. A battery backed real-time clock provides local time, UTC time, Julian date and sidereal time.

The versatile and powerful tour mode allows you to tailor your searches of the sky so that you may seek to find the types of objects that interest you the most, be they easy or highly challenging.

Though designed for standalone use, Argo NavisTM can also be interfaced to your PC, laptop, tablet or smartphone which brings about a wealth of additional features. It can operate with many of the popular sky charting packages to provide you with a tracking cursor display. Using the supplied ArgonautTM utility, it even lets you store into its FLASH memory over a thousand of your own user-defined objects including magnitudes and descriptions. You can erase them and store new ones as often as you like.

This User Manual shows how the Argo NavisTM Digital Telescope Computer can make your observing sessions more enjoyable and rewarding.



Contents

This manual 6

The Argo Navis interfaces. 8

The user interface. 8

The encoder interface. 9

The serial interface. 10

Initial setup of the Argo Navis. 12

Power sources. 12

Setting the initial mount type. 14

Setting encoder steps (resolution) 14

Setting altitude steps. 15

Setting azimuth steps. 15

Testing encoder communication. 16

Determining encoder direction senses. 17

Setting the final mount type. 18

Setting the local time zone, date and time. 20

Setting the location. 22

Setting refraction modelling. 24

Alignment procedures. 25

Purpose of alignment 25

Fork Exact Align and German Equatorial Exact Align Mounts. 25

Alt/Az Dobsonian Mounts including on Equatorial Tables. 26

Fork Rough Align Mounts. 28

GEM Rough Align. 29

An introductory run. 32

Operating modes. 37

MODE ALIGN.. 38

MODE ALIGN STAR.. 40

MODE AZ ALT. 44

MODE CATALOG.. 45

MODE ENCODER.. 52

MODE EQ TABLE.. 56

MODE FIX ALT REF. 59

MODE IDENTIFY.. 63

MODE RA DEC.. 69

MODE SETUP.. 71

MODE SIDEREAL. 73

MODE STATUS.. 74

MODE TIME.. 75

MODE TIMER.. 76

MODE TOUR.. 77

SETUP ALIGN PICK.. 84

SETUP ALT REF. 86

SETUP ALT STEPS.. 88

SETUP ARCHIVE.. 89

SETUP ATLAS.. 94

SETUP AZ STEPS.. 96

SETUP BRIGHTNESS.. 97

SETUP CONTRAST. 98

SETUP DATE/TIME.. 99

SETUP DEBUG.. 102

SETUP DEFAULTS.. 103

SETUP ENC TIMING.. 104

SETUP EQ TABLE.. 107

SETUP GOTO.. 109

SETUP GUIDE MODE.. 112

SETUP LCD HEATER.. 115

SETUP LOAD CAT. 116

SETUP LOCATION.. 118

SETUP MOUNT. 121

SETUP MNT ERRORS.. 122

SETUP REFRACTION.. 150

SETUP SCRATCH.. 152

SETUP SCROLL. 154

SETUP SERIAL. 155

Argonaut software utility Version 2.0. 159

ArgonautTM Version 2.0 introduction. 159

What does ArgonautTM do?. 159

What else do I need besides ArgonautTM?. 159

Installing ArgonautTM. 160

Launching ArgonautTM. 168

Establishing communication. 168

Where to obtain Asteroid, Comet or Satellite Orbital Element Files. 173

How to create your own User catalog files. 174

Transferring catalog files. 176

Updating catalog entries. 179

Deleting loadable catalogs. 180

Querying loadable catalog free memory. 181

Transferring setups. 181

Transferring firmware files. 186

Setting the date/time from your PC to Argo NavisTM. 188

Scaling the Argo NavisTM time-of-day clock. 190

LinuxTM operating system file transfer utilities. 196

Mac OS XTM operating system file transfer utility. 197

Using Argo Navis with the ServoCAT Track/GOTO Controller 198

ServoCAT introduction. 198

Interfacing to ServoCATTM and setups configuration. 198

Operation with ServoCATTM. 199

SmartTrackTM. 199

Tracking artificial satellites. 200

Programmer’s reference. 203

asteroid. 204

comet 205

date. 206

enc. 207

encctl 208

event 209

fp. 210

meade. 211

navis. 213

pbt 214

rad. 215

samples. 216

satellite. 217

servocat 218

setups. 219

sitech. 220

skycomm.. 221

tangent 222

therm.. 223

uptime. 224

user 225

Appendix A—Catalogs. 226

Appendix B—Technical specifications. 228

Appendix C—Port pin descriptions. 230

Appendix D—Factors that affect pointing accuracy. 231

Appendix E—Factors that affect encoder direction senses. 232

Appendix F—How to replace the lithium coin cell battery. 233

Appendix G—Troubleshooting guide. 236

Appendix H—How Argo Navis orders its symbols. 239

Appendix I—World time zones. 240

Appendix J—Warranty. 249

Appendix K—Conformance. 251

Appendix L—Glossary. 254

Index. 258

 


This manual

 


This section describes the content of the manual and how to use it.

Introduction

This manual is divided into 10 main sections:

·         How to use this manual

·         The Argo NavisTM interfaces

·         Initial setup of the Argo NavisTM;

·         Alignment procedures

·         An introductory run

·         Operating modes

·         The ArgonautTM software utility

·         Using Argo NavisTM with the ServoCAT Track/GOTO controller

·         Programmer’s reference

·         Appendices

Content of the manual

The Argo NavisTM interfaces describes the front panel of the Argo NavisTM, including the DIAL, the EXIT and ENTER buttons, and the ports on top of the Argo NavisTM.

Initial setup of the Argo NavisTM describes the once-only requirements for setting-up the Argo NavisTM to suit your mount-type and your individual requirements.

Alignment procedures describes how to align Argo NavisTM rapidly for use each night.

An introductory run describes how to use the Argo NavisTM to find objects once the initial setup has been performed and Argo NavisTM have been aligned.

Operating modes describes the purpose of each mode in the Argo NavisTM firmware and how to use them, and provides examples.

The ArgonautTM   software utility describes the use of the supplied ArgonautTM program, which runs on a PC. This software allows you to download to your unit asteroid, comet and satellite orbital elements as well your own user catalogs. You also use ArgonautTM to upgrade your Argo NavisTM firmware and in-built catalogs.

The Using Argo NavisTM with the ServoCAT Track/GOTO controller section describes how to interface Argo NavisTM with a ServoCAT to provide fully motorized operation of your mount.

The Programmer’s reference is designed for software developers who would like to write applications that can interface with Argo NavisTM.

The Appendices contain additional information on the Argo NavisTM.

How to use this manual

Don’t be daunted by the size of this manual. If you just want to get going, it is suggested that you read:

·         Initial setup of the Argo NavisTM;

·         Alignment procedures and

·         An introductory run

If you want to know all of the features of the Argo NavisTM, it is suggested that you read all of the chapters sequentially.

Don’t forget there is a glossary and an index if you need it, and the operating modes are all fully described. If you are reading this manual online as a PDF file, be sure to make use of the hyperlinks and the Acrobat Bookmarks navigation menu to help find your way around. Watch for updates of this manual at the Wildcard Innovations web site.



The Argo Navis interfaces


Figure 1 (Argo NavisTM Model 102B shown)

 

This section describes the various interfaces of the Argo NavisTM.

Types of interface

The Argo NavisTM has 3 interfaces:

Each type of interface is described below.

The user interface

The user interface is the front panel and consists of five elements as shown in Figure 1.

The ON/OFF switch is located at the top, left-hand of the front panel - ON is marked with “I”; OFF is marked with “O”.

The LCD is the horizontal window located near the top of the front panel. When the power is off the LCD will appear to be a blue colour. When the power is on the display will appear to be a red colour. Argo NavisTM uses a red display because this colour is less likely to impact upon your night vision, which is important when you want to view faint celestial objects. The brightness of the display can also be altered to suit your current viewing conditions (see page setup brightness).


Firmware” is the term used to describe the software in an electronic appliance. The Argo NavisTM firmware is organized as a set of menus which you can navigate by using the DIAL and the ENTER and EXIT buttons.

The DIAL is located in the centre of the front panel. It is used to scroll through the menus, to alter an item within a menu and to manually scroll long text messages. The DIAL has what are known as “detent clicks” (see Glossary). Sometimes you will need to move the DIAL one detent “click” at a time.

The ENTER button is located on the right-hand side of the front panel. It is used to enter a particular menu you have selected with the DIAL and to select a particular item within a menu.

The EXIT button is located on the left-hand side of the front panel. It is used to exit from menu selections.

 

The encoder interface

Figure 2  (Argo NavisTM Model 102B shown)

The encoder interface is the receptacle found on top of the unit and marked by the label “ENCODERS”.  See Figure 2. If you study your encoder cable, you will find one end has an 8-way RJ-45 plug from which two 4-way cables split. Insert this plug into the encoder interface receptacle.

If you have an encoder cable assembly supplied by Wildcard Innovations, the 4-way cable that has a white sleeve near the encoder end will go to the Altitude axis encoder. The other 4-way cable will go to the Azimuth axis encoder.

The Argo NavisTM Digital Telescope Computer (DTC) encoder interface was designed to be pin and electrically compatible with that used on the older JMI NGC-MAXTM, Celestron Advanced AstromasterTM, Lumicom Sky VectorTM, SkyComm Engineering Sky CommanderTM and similar Digital Setting Circle (DSC) units. Therefore, if you are upgrading to an Argo NavisTM from one of these older units, you can retain your existing encoders and cable. Note, however, that the Argo NavisTM supports a higher encoder sampling rate than these older units and therefore will reliably support higher resolution encoders. Though Argo NavisTM will work with lower resolution encoders, Wildcard Innovations recommends that you consider upgrading to 10,000 step encoders if you would like to achieve potentially finer pointing accuracy.

 

The serial interface

Argo NavisTM has two RS-232 serial ports on top of the unit marked SERIAL1 and SERIAL2. See Figure 2. Argo NavisTM can be used completely standalone. However, it is also possible to interface it to a PC, MacintoshTM or Linux computer assuming your PC/Mac has an RS-232 serial port or a USB port.

To interface to a computer with an RS-232 serial port use the Argo NavisTM serial port cable (Wildcard Innovations Part No. pn-ser-cbl).

If your PC/Mac does not have a RS-232 serial port but is equipped with a USB port, Wildcard Innovations have available a USB to RS-232 Serial Port Adaptor (Wildcard Innovations Part No. pn-usb) which works in conjunction with the optional RS-232 serial cable (pn-ser-cbl).

By communicating with your PC/Mac, you can perform the following tasks:

 

 Argo NavisTM can communicate to an Android™ tablet or iPad™ or to a smartphone/iPhone™ by interfacing the Argo NavisTM serial port cable (Wildcard Innovations Part No. pn-ser-cbl) to third party serial to WiFi adapters such as the Microchip/Roving Networks RN-340 and RN-370 or third party serial to Bluetooth adapters such as the Microchip/Roving Networks RN-270M. It can then be used with apps such as Sky SafariTM.

 

Argo NavisTM serial ports can be interfaced to ServoCAT™ servo controllers, Starmaster Star Tracker™ GOTO controllers and Sidereal Technology SiTech™ GOTO controllers. In each instance, a special serial cable, distinct from the Argo NavisTM serial port cable (Wildcard Innovations Part No. pn-ser-cbl), needs to be used. Contact Wildcard Innovations for details as to the correct cable to use.

 

The two serial ports operate completely independently.  Their Baud rates (communications speeds) can be set from the Argo NavisTM front panel. See the setup serial page.

 

For all operations, except downloading new firmware, either serial port can be used. For downloading firmware, SERIAL1 is special and is the only port that can be used for this purpose.

 

WARNING: The pin assignment on the Argo NavisTM serial ports is not compatible with those of the SkyComm Engineering Sky CommanderTM. However, they are compatible with those on the JMI NGC-MAXTM, Celestron Advanced AstromasterTM, Lumicom Sky VectorTM and similar Digital Setting Circle (DSC) units.  (See Port pin descriptions). To avoid possible damage to your Argo NavisTM or PC, we recommend you use only a genuine Argo NavisTM optional serial interface cable (Wildcard Innovations Part No. pn-ser-cbl).

 

WARNING: When interfacing your Argo NavisTM to a PC, you should be aware of the possibility of electrostatic discharge that could result in damage to your Argo NavisTM, PC and associated peripherals. Be sure to ground yourself adequately prior to interfacing any two pieces of equipment. Be particularly careful in static prone environments, especially in low humidity conditions or while walking on carpets. Wildcard Innovations bears no liability for loss or damage caused to your equipment from static discharge.

 

WARNING: It is your responsibility to ensure that any cables connected to your Argo NavisTM do not pose a hazard to yourself and others. Ensure that it is not possible for yourself or others to trip over your cabling. You should be aware that cabling could be a hazard to persons especially at night-time and when outdoors. Wildcard Innovations bears no liability for loss, damage or injury caused by persons tripping over your cabling.



Initial setup of the Argo Navis


 

                       Figure 3 (Argo NavisTM Model 102B shown)

This section describes the once-only requirements for setting-up the Argo NavisTM to suit your scope and your individual requirements. This includes:

·         setting your final mount type;

·         setting the local time zone, date and  time;

·         setting your location;

·         enabling refraction modelling;

Power sources

There are two types of power source:

·         external battery power.

Internal Battery Power

4 “AA”, 1.5V batteries provide the internal battery power. These should be alkaline, lithium or rechargeable NiMH batteries. Since NiMH batteries have reduced capacity below 20C (68F), their use is not recommended in cool or cold climates. Do not use NiCd or regular/ heavy-duty zinc-oxide batteries.

To install batteries, refer to Figure 3. Using a coin, remove & retain the battery hatch thumbscrew on the battery housing (the raised section at the top of the back) of the Argo NavisTM. Gently slide the battery cover slightly toward the top of the unit by about 1cm and then lift it off.

 

To place the batteries in, refer to Figure 4. Observe the polarity indicators inside the battery housing (+ on the battery should be placed at the same end as the + on the markings inside the battery housing). Replace the battery hatch cover and thumbscrew.

·         Ensure batteries are removed from the Argo NavisTM if it is to be stored or not used for prolonged periods in case of battery leakage.

·         Do not charge rechargeable batteries whilst in battery housing.

·         Do not connect any other form of power supply to battery terminals.

Fresh alkaline batteries with the display fully dimmed can provide from 12 to 40 hours usage of the unit depending on several additional factors including what type of encoders are installed.

 

External battery power

The optional external DC power cable allows you the convenience to power the Argo NavisTM from an external battery source such as a 12V car battery.  The external power receptacle is found on the top of the unit and is marked DC IN. The external battery voltage should be in the range of 8V to 16V DC. An incorrect power voltage source or polarity could cause damage to your unit and void your warranty. Use only the optional external DC power cable supplied by Wildcard Innovations (Part No. pn-pwr-cbl) for supplying external power to your unit. Though Argo NavisTM provides in-built reverse polarity and short circuit protection, the optional cable contains a 350mA fuse for additional safety.

 

WARNING: Never use a cable with an incorrect fuse (we recommend 315mA) and never bypass the fuse protection. Observe all safety procedures when working with external batteries. Many contain dangerous acids that can be spilt and some batteries are capable of delivering very large currents that can destroy equipment or cause a fire if they are short-circuited.

 

WARNING: Be careful not to trip or allow others to trip over the external power cable or any other cables from your unit.

Figure 4  (Argo NavisTM Model 102B shown)


Setting the initial mount type

Argo NavisTM requires you to specify what style of mount your telescope is on.

However, for the purpose of this once-only initial setup procedure, you will be asked to set your mount type to the fork exact align setting, irrespective of what type of mount you really have.

Later, you will be asked to set the mount type to match the type of mount you are using.

Power the unit on. Turn the DIAL clockwise until you see -

 

MODE SETUP

 

Press ENTER. Now turn the DIAL clockwise until you see -

 

SETUP MOUNT

 

Notice how Argo NavisTM orders its various menus alphabetically so you can find a particular one logically and quickly.

Now press ENTER. The display might then show -

 

ALTAZ/DOBSONIAN

 

where the whole line will be flashing. Spin the DIAL until the display shows –

 

FORK EXACT ALIGN

 

Then press EXIT or ENTER. Argo NavisTM will briefly display the words

 

SAVING ….

 

while it saves your settings into its memory (EEROM device) and then display the message –

 

SETUP MOUNT

Setting encoder steps (resolution)

Before you can perform an alignment, you need to set up in Argo NavisTM the resolution and “direction senses” of your altitude and azimuth encoders.

 

Encoder operation background

Most optical encoders will have a printed label specifying either their part number or their resolution. For example, if you have an encoder marked with the part number S2-2500, this is a 10,000-step encoder (10,000 is 4 times 2500 - this style of encoder is technically known as a Quadrature Encoder).

When an encoder rotates, it transmits electrical pulses or ‘steps’. A 10,000-step encoder will produce 10,000 steps when it is rotated 360°. Therefore, one ‘step’ on such an encoder corresponds to an angle of rotation of about 2.16 arc minutes.

Encoders can be geared to produce a higher or lower number of ‘steps’ when the telescope mount bearing they are attached to rotates through 360°.

In any case, you need to establish how many steps your encoders produce when the bearing they are attached to is rotated through 360°. In many cases, bearings, particularly altitude (declination) bearings, may be incapable of being rotated through a full 360°. Nonetheless, you will still need to establish how many steps the encoder would produce if the bearing could be rotated through a full 360°.

If the shaft of your encoder is attached directly to the axis of rotation of the bearing and is not geared, then the number of steps for that particular encoder is simply its rated number of steps.

Setting altitude steps

Having established how many steps each encoder is, spin the DIAL within the setup menu-level until you see -

 

SETUP ALT STEPS

 

Press ENTER and the display might show something like this -

 

ALT=+0010000

 

where the ‘+’ sign will be flashing. Leave the sign as a ‘+‘ for now and press ENTER and edit the fields as need be by using the DIAL to change a value and ENTER to advance to the next field. When the correct number of steps is displayed, press either ENTER or EXIT and if the value has changed from what it originally was, Argo NavisTM will briefly display the words -

 

SAVING ….

 

while it saves your settings into its memory (EEROM device) and then display the message –

 

SETUP ALT STEPS

 

You have now set your altitude encoder step setting. However, as will be explained later, you may need to come back and change the encoder ‘direction sense’ (the ‘+’ sign or  -’ sign) depending upon your circumstances.

Setting azimuth steps

Using the DIAL, go to -

 

SETUP AZ STEPS

 

Press ENTER again and the display might show something like this -

 

AZ=+0010000

 

where the ‘+’ sign will be flashing. Leave the sign as a ‘+‘ for now and press ENTER and edit the fields as need be by using the DIAL to change a value and ENTER to advance to the next field. When the correct number of steps is displayed, press either ENTER or EXIT and if the value has changed from what it originally was, Argo NavisTM will briefly display the words -

 

SAVING ….

 

while it saves your settings into its memory (EEROM device) and then display the message –

 

SETUP AZ STEPS

 

You have now set your azimuth encoder step setting. However, as will be explained later, you may need to come back and change the encoder ‘direction sense’ (the ‘+’ sign or  -’ sign) depending upon your circumstances.


Testing encoder communication

Power Argo NavisTM off. Make sure that your encoders are installed on your mount and that your encoder cable is connected both to them and into the ENCODERS port of the Argo NavisTM. (See Figure 2.)

Power Argo NavisTM on and use the DIAL to go to -

 

MODE ENCODER

 

Press ENTER. The display should show something like this –

 

AZ/ALT ENC ANGLE

000.00° +000.00°

 

The display is showing the angle of the azimuth encoder on the bottom left of the display and that of the altitude encoder on the bottom right.

Move the scope in azimuth (Right Ascension). Make sure that the AZ angle on the display changes. Now move the scope in altitude (Declination). Make sure that the ALT angle changes. If the ALT reading changes when you move the scope in azimuth and vice versa, you have the encoder cables swapped around. On most encoder cables supplied by Wildcard Innovations, the cable that has the white sleeve near its encoder end should go to the altitude encoder.

If neither or only one angle changes on the display check that the connections to the encoders are correct, in particular making sure that the plug that connects to the encoder pin header is inserted the right way up. On encoders and cables supplied by Wildcard Innovations, the correct orientation can be ascertained by matching the small circular sticker on the plug with the same type of sticker on top of the encoder (the side opposite that from which the shaft protrudes). Also, ensure that any set-screw holding the encoder shaft in place is firm and is not allowing the encoder shaft to slip. Finally, check the batteries in your Argo NavisTM   and replace them if necessary.

 

If you are performing the above test without having installed the encoders on your mount and you are simply turning the encoder shafts with your fingers, you may see one of the following messages on the display –

 

·         AZ ENCODER ERROR

·         ALT ENCODER ERR

·         BOTH ENCODER ERR

 

This simply means that you have turned the encoders too quickly and have exceeded their sampling rate, thus missing counts. Argo NavisTM   typically samples the encoders at a very high rate (much higher than older Digital Setting Circle, or ‘DSC’, units) and when the encoders are installed on your mount, you should not see these errors during normal operation. If the encoders are installed on your mount and you do see these errors, check the batteries in Argo NavisTM   and the connections on your encoders. Otherwise see the Troubleshooting guide.

 

Once you have established that your Argo NavisTM   can reliably communicate with your encoders, you are ready to proceed.

Determining encoder direction senses

When you were initially setting your encoder resolution with setup alt steps and setup az steps, you were asked to ignore the flashing +’ sign. Using the DIAL, the sign can be made to be either a ‘+’ or a ‘-’.  It determines the way that Argo NavisTM interprets the ‘direction sense’ of the applicable encoder.

Setting the correct direction senses of your encoders is very important. Many factors influence the setting of encoder direction senses. For example, in the case of an altitude encoder, whether it is mounted on the left or right-hand side of the mount and whether it has been geared an even or odd number of times are just two of the factors. The section named Factors affecting encoder direction sense details these. For this reason, determining the correct direction senses of your encoders may not be simply intuitive. Fortunately, you can perform a test with your scope that will tell you what the correct senses are. Once you have patiently worked through the test and have determined the correct settings for the encoders on your mount, you should never need to change them again.

To determine the direction senses of your encoders, follow these instructions.

Power off your Argo NavisTM, and then power it back on. After it initializes, you should see –

 

MODE ALIGN STAR

then press ENTER. The display should show something like -

 

ALIGN ACHERNAR

 

If your scope is on a Fork Mount, roughly polar align it. Orient the tube so that it is the “way-up” you normally observe, thus –

Figure 5

 

 

If your scope is on a German Equatorial Mount (GEM), roughly polar align it. If you are in the Northern Hemisphere, place the tube on the West side of the mount. If you are in the Southern Hemisphere, place the tube on the East side of the mount.

If your scope is on an Alt/Az Mount, such as a Dobsonian, just continue reading. If your Alt/Az mount is mounted on top of an equatorial table, accurately polar align the table, move the table to the start position and switch it off for now.

Look up at the sky and pick a familiar bright star not far from the Celestial Equator (the imaginary line in the sky where Declination = 0°.) Spin the DIAL and look for that star’s name. There are 35 to choose from. The mode align star reference page lists the alignment stars. If you cannot find the star you have chosen in the list, pick another that is in the list that is not too far from the Celestial Equator. For example, say you have chosen Sirius. Spin the DIAL until you
see -

 

ALIGN SIRIUS

 

Centre Sirius in the eyepiece, then press ENTER. The display will briefly show something like this –

 

ALIGN SIRIUS

WARP=  +0.00

 

Now press EXIT and spin the DIAL until the display shows –

 

MODE RA DEC

then press ENTER. The display should show the approximate Right Ascension and Declination of the last star you aligned on. In the example of Sirius, the display might show something like this -

 

06:45.3 -16°43’

CANIS MAJOR

 

While watching the RA reading on the display, rotate the scope slowly in an Easterly direction. The RA value should increase. If instead it decreases, take note of that fact and continue for now.

While watching the Dec reading on the display, rotate the scope slowly in a Northerly direction. The Dec value should increase (a negative Dec value that becomes more and more negative is in fact decreasing). If the Dec value is decreasing, take note of that fact and continue.

If the Right Ascension and Declination directions were consistent with the above procedure, you do not need to alter the setup alt steps or setup az steps direction senses.

If the Right Ascension reading decreased as the scope was moved towards the East, then go back to setup az steps and change the direction sense sign.

If the Declination reading decreased as the scope was moved towards the North, then go back to setup alt steps and change the direction sense sign.

If you changed either or both signs, power the unit off and then on and repeat the procedure to verify that the new encoder direction senses are correct.

Setting the final mount type

During the initial once-only setup procedure, you were asked to set the mount type to fork exact align. You will now need to set your mount type to match your actual mount. If you have a Fork mount that is exactly polar aligned, you obviously do not need to change the setting.

Otherwise, power the unit off, then on. Turn the DIAL clockwise until you see -

 

MODE SETUP

 

Press ENTER. Now turn the DIAL clockwise until you see -

 

SETUP MOUNT

 

Now press ENTER. The display should show -

 

FORK EXACT ALIGN

 

where the whole line will be flashing. Spin the DIAL and select your mount type. The various mount types are tabled below.

Menu selection

When to use

Number of alignment stars required

ALTAZ/DOBSONIAN

For altitude/azimuth mounts such as Dobsonians (but not on equatorial tables);

fix alt ref step plus 2 alignment stars

EQ TABLE EXACT

For altitude/azimuth mounts mounted on top of an accurately polar aligned equatorial table

fix alt ref step plus 2 alignment stars

FORK EXACT ALIGNED

For any accurately aligned equatorial mount, such as a fork mount, but not a German equatorial or an equatorial table.

One alignment star

FORK ROUGH ALIGN

For any roughly aligned equatorial mount, such as a fork mount, but not a German equatorial or an equatorial table.

fix alt ref step plus 2 alignment stars

GEM EXACT ALIGN

For an accurately polar aligned German equatorial.

One alignment star

GEM ROUGH ALIGN

For a roughly aligned German equatorial.

fix alt ref step plus 2 alignment stars

 

Once you have selected your mount type, press either EXIT or ENTER. Argo NavisTM will briefly display the words

 

SAVING ….

 

while it saves your settings into its memory (EEROM device) and then display the message –

 

SETUP MOUNT

 


Setting the local time zone, date and time

Argo NavisTM contains an in-built battery-backed time of day clock. An internal lithium coin cell battery powers the clock even when the power is switched off or the main batteries are removed.

Though Argo NavisTM does not require you to set the time or your location to operate, doing so provides the following additional features and benefits:

·         The Local Apparent Sidereal Time (LAST) will be available to you in mode sidereal if you have also specified your location.

·         The topocentric azimuth and altitude (see Glossary) will be available to you in mode az alt assuming you have also specified your location and have performed a valid star alignment.

·         The horizon mask filtering option will be applied correctly in mode identify and mode tour assuming that you have also specified your location.

·         If in setup guide mode the guide below horz setting has been set to h indicator on, then anHsymbol will appear on the guide mode display whenever an object is computed to be below the computed horizon, which in turn also assumes that you have specified your location.

·         Correction for atmospheric refraction (see Glossary) will be made while you point your scope assuming you have also specified your location and assuming you have turned refraction correction on in the setup refraction sub-menu.

·         Objects will be precessed and nutated (see Glossary) from their internally stored J2000.0 epoch positions to their actual position at the time you observe them.

·         The positions of planets can be accurately determined.

·         The positions of asteroids and comets can be computed from their orbital elements.

·         The position of earth orbiting satellites can be computed assuming you have also specified your location.

·         If you have a ServoCATTM slew and track system, Argo NavisTM will provide horizon limit checking when running the “servocatstartup command on the Argo NavisTM serial port. Horizon limit checking also assumes you have specified your location.

For these reasons it is worthwhile setting your local time zone, date and time. Since Argo NavisTM retains the time even when it is powered off, you only need do it once and then possibly occasionally to correct for normal clock drift.

 

To set the local time zone, date and time, perform the following. Power the unit on. Turn the DIAL clockwise until you see

 

MODE SETUP

 

Press ENTER. Now turn the DIAL clockwise until you see

 

SETUP DATE/TIME

 

Notice how Argo NavisTM orders its various menus alphabetically so you can find a particular one logically and quickly.

 

Press ENTER. Argo NavisTM will display something like

 

TIMEZONE=+00:00

 

Where the ‘+’ (or possibly ‘-‘) sign will be flashing.

 

To understand the concept of time zone, it is important to know that Argo NavisTM always internally keeps track of time in terms of Universal Co-ordinated Time (UTC), which was previously referred to as Greenwich Mean Time (GMT). The time zone is the number of hours that your local time differs from UTC. For example, in New York when Daylight Savings Time (Summer time) is not in effect, the time zone setting is 
-05:00 hours. When Daylight Savings (summer time) is in effect, the time zone is –4:00. In Sydney, when Daylight Savings time is not in effect, the time zone setting is +10:00 hours and when Daylight Savings is in effect +11:00. In New Delhi the time zone is +05:30.

 

Use the World timezones section of this manual to determine your local time zone. If you are in a time zone that is west of Greenwich, you will set the sign to a ‘-‘. If you are in a time zone that is east of Greenwich, you will set the sign to a ‘+’.

 

By turning the DIAL you can change the sign alternately between a ‘+’ and a ‘-‘. When you have selected the correct sign, hit ENTER, which advances the flashing ‘cursor’ to the first numeric field. You can change the value in that field by turning the DIAL. When you have selected the correct value, advance the cursor to the right by hitting the ENTER button again and so on.  When you have finished editing the last field (most people will live in a time zone that is only a whole number of hours offset from UTC), pressing the ENTER button again will result in a display something like

 

DATE=24 APR 2015

TIME=15:30:45

 

where the first digit will be flashing. Again, as in editing the time zone, edit the correct local date and time by using the DIAL and pressing the ENTER button to advance over fields. If you make a mistake, press EXIT and start over again. Keep in mind that you are entering your local date and time here, not the UTC time. Argo NavisTM will perform the appropriate arithmetic to convert the date and time you enter to internal UTC time by taking into account the time zone you entered.

 

When you have edited the last field, you may like to synchronize the pressing of the ENTER button against some correct time reference. Argo NavisTM will then briefly display the words

 

SAVING ….

 

and then the words

 

INITIALIZING ….

 

in the lower half of the display before returning to the setup sub-menu with the message

 

SETUP DATE/TIME

 

You have now successfully set your local time zone and your local date and time.

 

While the SAVING message appeared, Argo NavisTM saved your time zone setting into its memory (EEROM  device) and the date and time into the battery backed time-of-day clock. While the INITIALIZING message appeared, Argo NavisTM re-initialized such things as the positions of planets, asteroids and comets and recalculated the amount of precession and nutation to account for since the J2000.0 epoch.

It is handy to remember that whenever Daylight Savings comes into or out of force in your locality, simply edit the time zone by adding or subtracting an hour from it as necessary. There is no need to change the local time as changing the time zone will automatically perform the correct arithmetic.

Normally the lithium coin cell battery used by the time of day clock should last for several years. If for any reason it should run flat, when Argo NavisTM is powered on, it will display briefly this message

 

RTC BATTERY FLAT

 

Followed by this message -

 

SETTING DATE TO

12:00 1 JAN 2000

 

See the section How to replace the lithium coin cell battery for details.

 

Setting the location

As was discussed in the section on setting the time zone, date and time, Argo NavisTM does not require you to set your location to operate, however, doing so brings about other features and benefits.

 

While in mode setup, turn the DIAL until you see -

 

SETUP LOCATION

 

Then press ENTER, where you will then see a location name such as this

 

NOWHERE,ATLANTIC

 

If you turn the DIAL you will then see the names of 10 locations in the world. If you happen to live in one of them, simply hit EXIT while its name appears in the display and you are done.

 

Chances are, however, that you do not live in any of the locations indicated. This is not a problem, since you can edit the locations to places that you observe from. For example, say you are unlikely to do any observing from Mawson Base in Antarctica. Let us edit the ‘mawson base’ location to ‘home’.

 

While in setup location, Turn the DIAL until

 

MAWSON BASE

 

appears on the display The whole line will be flashing.

 

Now press the ENTER button. You have now entered location name edit mode. The ‘M’ character will be flashing indicating that the cursor is at that location. Turn the DIAL anti-clockwise until the letter ‘H’ appears, then press ENTER to advance to the next letter, which is an ‘A’. Turn the DIAL in either direction to make it a ‘O’, press ENTER, and so on until you have spelt out the word ‘HOME’. Continue to erase the rest of the characters in the old mawson base name by turning them into SPACES. The SPACE character is found just after the letter ‘Z’ if you are turning the DIAL clockwise. When you have erased the last character, press ENTER multiple times until the display shows this

 

LAT=67:35:59 S

 

This is the latitude of Mawson Base which you will now change to your local latitude. To determine your local latitude, consult an atlas or one of the many location databases (such as www.heavens-above.com) available on the Internet. Unless you plan on observing satellites, or accurately knowing your Local Apparent Sidereal Time (LAST), don’t be too concerned if you cannot determine the exact co-ordinates of your location. Within a degree or so should be fine for most situations.

 

Using the DIAL and ENTER button, edit the latitude fields to values appropriate for your observing location. Latitude is displayed in terms of degrees:minutes:seconds either North or South of the Earth’s equator. Change the ‘S’ to an ‘N’ depending upon whether your location is in the Northern or Southern Hemisphere.

 

After editing the North/South field, pressing ENTER again will result in the display showing this

 

LONG=062:53:00 W

 

This is the longitude of Mawson Base. Edit it as you did the Latitude, replacing the fields with values appropriate to your observing location. Longitude is displayed in terms of degrees:minutes:seconds either East or West of Greenwich. Change the ‘W’ to an ‘E’ depending upon whether your location is East or West of the Greenwich Meridian. For example, if you live in the United States or Canada, your location will be West of Greenwich so you will enter a ‘W’. If you live in Australia, for example, your location will be East of Greenwich so you will enter an ‘E’.

 

When you have edited the last longitude field, press ENTER. The display will then show

 

HOME

 

where the word home will be flashing. Press EXIT to set home as your observing location. The display will briefly show

 

SAVING ….

 

And then the words

 

INITIALIZING ….

 

In the lower half of the display before returning to the setup sub-menu with the message

 

SETUP LOCATION

 

You have now successfully set your location.

 

While the SAVING… message appeared, Argo NavisTM saved your location settings into its memory (EEROM device). While the INITIALIZING … message appeared, Argo NavisTM re-initialized such things as the current Local Apparent Sidereal Time (LAST).

 

You can edit as many of the locations in the setup location menu as you desire. Whenever you change observing location, simply enter the
setup location menu, turn the DIAL until the name of the location you are observing from appears, then hit EXIT.

 

Remember, in order to perform an alignment and to use most of the features of Argo NavisTM you don’t need to set your time zone, date, time or location unless you also decide to turn on refraction modelling correction or would like some of the other features or benefits discussed earlier.

Setting refraction modelling

Due to the phenomenon of atmospheric refraction, celestial objects close to an observer’s horizon will appear to be higher in altitude than what they actually are. Argo NavisTM   can compensate for the effects of atmospheric refraction. However, to do so, Argo NavisTM   must have had the time zone, date, time and location set reasonably accurately. It uses these parameters in conjunction with information it will obtain once you perform an alignment, to determine where the observer’s local horizon is. Having determined that, it then can correct for refraction.

If you do not plan to observe objects close to the horizon, you may decide to leave refraction modelling off. However, if you are confident you have set your time zone, date, time and location correctly, it is a good idea to turn it on to improve your pointing accuracy.

To turn refraction modelling on, go to the

SETUP REFRACTION

 

sub-menu and press ENTER. The display might then show -

 

REFRACTION=OFF

 

where the word  OFF’ is flashing. Use the DIAL to change the setting to either ‘ON’ or ‘OFF’ as you desire. Then press either EXIT or ENTER to save that selection into memory (EEROM device) and to specify it as your current setting.

 


 


Alignment procedures


This section gives a quick introduction to the alignment procedure for Argo NavisTM. Variations and possible refinements to the alignment procedure are discussed in -

mode fix alt ref

setup alt ref

mode align star

mode align

mode eq table

setup align pick

setup refraction

and

 setup mnt errors.

 After reading this section, you are encouraged to read the sections just referenced to provide you with a fuller understanding of the alignment procedure. They are worth reading as the alignment procedures described here are simply meant to help you get started. A fuller understanding of the alignment procedure will help you improve your pointing accuracy.

Purpose of alignment

Whenever you power on Argo NavisTM you will need to carry out an alignment procedure in order for it to locate objects.

The alignment procedure depends on the type of mount you have and whether it is accurately polar-aligned or not. You should have already set your mount type in setup mount.

Fork Exact Align and German Equatorial Exact Align Mounts

The possible polar-aligned mount settings are fork exact align and gem exact align (for German Equatorials). The following procedure assumes that the mount has been accurately polar-aligned. If that is so, only one alignment star is required.

When Argo NavisTM is first powered on, after initializing, it will prompt you
with –

MODE ALIGN STAR

Press ENTER. The display should show something like -

 

ALIGN ACHERNAR

If you have a German Equatorial Mount, and are in the Northern Hemisphere, position the tube on the West side of the mount.

If you have a German Equatorial Mount and are in the Southern Hemisphere, position the tube on the East side of the mount.

If you have a Fork mounted scope, orient the tube the “normal” way up that you observe with it.

Look up at the sky and pick a familiar bright star. Spin the DIAL and look for that star’s name. There are 35 to choose from. The mode align star reference page lists the alignment stars. If you cannot find the star you have chosen in the list, pick another that is in the list.

Figure 6

 

Sight the star. If you have a German Equatorial mount and would like to sight the star with the tube on the opposite side of the mount, go to setup alt steps and change the direction sense sign. Whenever you wish to re-align using the scope on the original side of the mount, be sure to change the sign back.

Centre the star as accurately as possible in the centre of the eyepiece, not just the finder-scope. When the star is perfectly centred, press ENTER. For example, say you have chosen Sirius. The display will briefly show 

 

ALIGN SIRIUS

WARP=  +0.00

 

This completes the alignment procedure. Now go on to read An introductory run.

Alt/Az Dobsonian Mounts including on Equatorial Tables

If you have set your mount type to be alt/az dobsonian or eq table exact then use the following procedure. You will be required to perform an operation called fix alt ref and two star alignments.

If you are using an equatorial table, park the table to its start position and switch it off for now.

When Argo NavisTM is first powered on, after initializing, it will prompt you
with –

 

FIX ALT REF

 

Press ENTER. Turn the DIAL until you see -

 

ALT REF=90°

AUTO ADJUST OFF

 

Now move your telescope to a position in altitude so that the tube is pointing at right angles with respect to the base like thus-

The scope does not have to be level on the ground. Only the orientation of the tube to the base is important. If the telescope is sitting on an equatorial table, it is the orientation of the tube to the plane of the table that is important. Due to mechanical constraints in your mount, you may not be able to get the scope at exactly right angles. Try to get it as close as possible for now. Later on you can review the mode fix alt ref reference page that discusses the auto adjust on feature that can assist you with this procedure. It’s worth reading as this is a very important step that can dramatically improve your pointing accuracy.

When your tube is in this position, press ENTER. The display will briefly show -

 

ALT REF=90°

WARP=ALT FIX OK

 

Press EXIT. In the top-level menu, spin the DIAL until you see –

 

MODE ALIGN STAR

then press ENTER. The display should show something like -

 

ALIGN ACHERNAR

Look up at the sky and pick a familiar bright star. Spin the DIAL and look for that star’s name. There are 35 to choose from. Section mode align star lists the alignment stars. If you cannot find the star you have chosen in the list, pick another that is in the list. For example, say you have chosen Sirius. Spin the DIAL until you see -

 

ALIGN SIRIUS

 

Centre Sirius in the eyepiece, then press ENTER. The display will briefly show something like this –

 

ALIGN SIRIUS

WARP=  -4.75 (1)

 

Your “WARP” number will probably be different, but don’t worry. Now pick a second bright alignment star. Preferably choose one approximately 30° to 90° away from the first and which will involve having to move the scope in both axes. For example, say you have chosen Capella. Spin the DIAL until you see –

 

ALIGN CAPELLA

 

Centre Capella in the eyepiece, then press ENTER. The display will briefly show something like this –

 

ALIGN CAPELLA

WARP=  +0.12

 

Your “WARP” number should ideally be as close to 0.00 as possible. A number in the range of –0.5 to +0.5 will probably give you reasonable pointing accuracy depending upon the accuracy of your initial fix alt ref step and how far you move from the initial alignment stars.

If your WARP number was much larger you may want to check that you identified the correct stars and repeat the alignment procedure if need be. Otherwise see the Troubleshooting guide.

Only if you are using an equatorial table and you have set your mount type to be eq table exact, then perform the following steps to begin tracking

Press EXIT to go to the top-level menu and then spin the DIAL until you see –

 

MODE EQ TABLE

 

then press ENTER. The display should show this -

 

EQ TBL ELAPSED
00:00:00.0 STOP

 

Simultaneously start the table and press ENTER which will start the Argo NavisTM equatorial table timer. Refer to the section entitled mode eq table in order to learn more about how to successfully use your Argo NavisTM with an equatorial table.

This completes the alignment procedure. Be sure to take the time to read the section on mode fix alt ref. In particular you may want to come back and attempt to use the auto adjust on mode. It may well dramatically improve your alignment. Now go on to read An introductory run.

Fork Rough Align Mounts

Sometimes you may not want to align your Fork mount accurately but would still like to find objects. If you have set your mount type to be fork rough align, then use the following procedure. You will be required to perform an operation called fix alt ref and two star alignments.

When Argo NavisTM is first powered on, after initializing, it will prompt you
with –

 

FIX ALT REF

 

Press ENTER. Turn the DIAL until you see -

 

ALT REF=0°

AUTO ADJUST OFF

 

 

Roughly polar align your scope. Orient the tube as accurately as possible so that it is 90° with respect to the forks and the “way-up” you normally observe, thus –

 

Figure 7

 

When your tube is in this position, press ENTER. The display will briefly show -

 

ALT REF=0°

WARP=ALT FIX OK

 

Press EXIT. In the top-level menu, spin the DIAL until you see –

 

MODE ALIGN STAR

then press ENTER. The display should show something like -

 

ALIGN ACHERNAR

Look up at the sky and pick a familiar bright star. Spin the DIAL and look for that star’s name. There are 35 to choose from. The mode align star reference page lists the alignment stars. If you cannot find the star you have chosen in the list, pick another that is in the list. For example, say you have chosen Sirius. Spin the DIAL until you see -

 

ALIGN SIRIUS

 

Centre Sirius in the eyepiece, then press ENTER. The display will briefly show something like this –

 

ALIGN SIRIUS

WARP=  -1.75 (1)

 

Your “WARP” number will probably be different, but don’t worry. Now pick a second bright alignment star. Preferably choose one approximately 30° to 90° away from the first and which will involve having to move the scope in both axes. For example, say you have chosen Capella. Spin the DIAL until you see –

 

ALIGN CAPELLA

 

Centre Capella in the eyepiece, then press ENTER. The display will briefly show something like this –

 

 

ALIGN CAPELLA

WARP=  +0.20

 

Your “WARP” number should ideally be as close to 0.00 as possible. A number in the range of –0.5 to +0.5 will probably give you reasonable pointing accuracy depending upon the accuracy of your initial fix alt ref step.

If your WARP number was much larger you may want to check that you identified the correct stars and repeat the alignment procedure if need be. Otherwise see the Troubleshooting guide.

This completes the alignment procedure. Be sure to take the time to read the section on mode fix alt ref. In particular you may want to come back and attempt to use the auto adjust on mode. It may well dramatically improve your alignment. Now go on to read An introductory run.

GEM Rough Align

Sometimes you may not want to align your German Equatorial Mount accurately but would still like to find objects. If you have set your mount type to be gem rough align, then use the following procedure. You will be required to perform an operation called fix alt ref and two star alignments.

When Argo NavisTM is first powered on, after initializing, it will prompt you
with –

 

FIX ALT REF

 

Press ENTER. Turn the DIAL until you see -

 

ALT REF=0°

AUTO ADJUST OFF

 

 

Roughly polar align your scope.

If you are in the Northern Hemisphere, place the tube on the West side of the mount.

If you are in the Southern Hemisphere, place the tube on the East side of the mount.

If you are going to do the first star alignment with the tube on the opposite side of the mount, go to setup alt steps and change the direction sense sign. Be sure to change it back when you want to do a first-star alignment on the original side of the mount.

Set the tube so that the scope’s Optical Axis is at 90° with respect to the Polar Axis. Try to do this as accurately as possible.

When your tube is in this position, press ENTER. The display will briefly show -

 

ALT REF=0°

WARP=ALT FIX OK

 

Press EXIT. In the top-level menu, spin the DIAL until you see –

 

MODE ALIGN STAR

then press ENTER. The display should show something like -

 

ALIGN ACHERNAR

Look up at the sky and pick a familiar bright star. Sight the star in the scope without moving more than 90° in declination. That infers that you should not cross the North or South Celestial Pole in order to sight the first star. Spin the DIAL and look for that star’s name. There are 35 from which to choose. The mode align star reference page lists the alignment stars. If you cannot find the star you have chosen in the list, pick another that is in the list. For example, say you have chosen Sirius. Spin the DIAL until you see -

 

ALIGN SIRIUS

 

Centre Sirius in the eyepiece, then press ENTER. The display will briefly show something like this –

 

ALIGN SIRIUS

WARP=  -1.75 (1)

 

Your “WARP” number will probably be different, but don’t worry. Now pick a second bright alignment star. You can now move the telescope in any direction to sight it. Preferably choose one approximately 30° to 90° away from the first and which will involve having to move the scope in both axes. For example, say you have chosen Capella. Spin the DIAL until you see –

 

ALIGN CAPELLA

 

Centre Capella in the eyepiece, then press ENTER. The display will briefly show something like this –

 

ALIGN CAPELLA

WARP=  +0.20

 

Your “WARP” number should ideally be as close to 0.00 as possible. A number in the range of –0.5 to +0.5 will probably give you reasonable pointing accuracy depending upon the accuracy of your initial fix alt ref step and fabrication errors within your mount.

If your WARP number was much larger you may want to check that you identified the correct stars and repeat the alignment procedure if need be. Otherwise, read the Troubleshooting Guide and the introductory sections of setup mnt errors.

This completes the alignment procedure. Be sure to take the time to read the section on mode fix alt ref. Improving the accuracy by which you perform the fix alt ref operation will dramatically improve your pointing accuracy. In particular your attention is drawn to the auto adjust on feature of mode fix alt ref.

Now go on to read An introductory run.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 



An introductory run

 


This section gives a quick introduction as to some of the ways you might locate objects using your Argo NavisTM. It does so by way of examples. It assumes that you have successfully aligned the unit by following the instructions in Alignment procedures. It purposely doesn’t give a lot of detail as to how things work (that is covered in detail in the Operating modes section). However, by following the directions, you should quickly learn by this ‘hands-on’ experience. Each example builds on the previous example, so it is best to follow them in order. The objects in the examples may not be viewable from your site, or when you perform a search you may not find the same ones, but you should still be able to grasp the basic ideas.

Argo NavisTM provides a great deal of flexibility and power in the many ways it can help you locate or identify objects. For a more detailed discussion of these methods, it is recommended you read the following reference pages –

mode catalog

mode identify

mode ra dec

mode tour

 

Examples

Example 1 – You want to locate the Messier object M53, assuming it is above the horizon.

You have already aligned your scope. Enter mode catalog by spinning the DIAL in the top-level menu and pressing ENTER when you see –

 

MODE CATALOG

 

appear on the display. You will be prompted by a message such as –

 

BRIGHT STARS

 

where those words will be flashing.

The catalogs are listed in alphabetical order. Spin the DIAL clockwise and cycle through the list of available catalogs until you see –

 

MESSIER

 

then press ENTER. Spin the DIAL clockwise until the display shows -

 

M5

 

then press ENTER. Spin the DIAL clockwise until the display shows –

 

M53

 

then press ENTER again. The display might show something like this –

 

M53

GUIDE 45®  25¯

 

Now move the scope in Azimuth (Right Ascension on a polar aligned scope) and try to make the first set of digits as close to 0.0 as possible. For example –

 

 

M53

GUIDE 0.0 25¯

 

Now move the scope in Altitude (Declination on a polar-aligned scope) and try to make the second set of digits as close to 0.0 as possible. For example –

 

M53

GUIDE 0.0 0.0

 

Now look through the eyepiece and hopefully there is your object!

 

Now press ENTER again. You will see a scrolling description of the object -

 

M53 ALSO KNOWN AS NGC 5024 GLOBULAR CLUSTER IN COMA BERENICES SIZE=12.6’ MAG=7.6 RA=13:12:56 DEC=+18°10’08” 2000.0 ABOVE HORIZON HB=C29

 

While the message is being displayed, you can grab the DIAL and scroll the text back and forth if you so desire. When you have finished reading it, press ENTER or EXIT and the display will return to guide mode.

 

M53

GUIDE 0.0 0.0

 

Now press EXIT again and return to –

 

MODE CATALOG

 

Example 2 – You want to locate the Sombrero Galaxy, assuming it is above the horizon. You know it has both a Messier and NGC number, but you have forgotten both.

Enter mode catalog and spin the DIAL until you see –

 

POPULAR DEEP SKY

 

Then press ENTER. Spin the DIAL to make the first character an ‘S’, then press ENTER. Now spin the DIAL and make the second character an ‘O’, then press ENTER. Now make the third character an ‘M’, then press ENTER. You should now have a display similar to this –

 

SOMBRERO GALAXY

GUIDE 5®0 7­3

 

You can then guide to it as you did in the previous example.

You may have noticed while you were spelling out the name of SOMBRERO GALAXY using the DIAL and the ENTER button, that Argo NavisTM prompted you with the names of other objects that matched your partial input at each point along the way. Once enough characters had been entered to uniquely match the object name you were after, you were guided to it straight away without requiring any more input. This is known as the Intelligent Editing SystemTM.

If you press ENTER, you will get the scrolling description.

 

SOMBRERO GALAXY ALSO KNOWN AS M104 ALSO KNOWN AS NGC 4594 GALAXY IN VIRGO SIZE=8.7’x5.3’ MAG=7.6 SB=12.1 MORPH=SA(s)a sp SOMBRERO GALAXY RA=12:40:00 DEC=-11°37’21” J2000.0 ABOVE HORIZON HB=D31,C48

 

Therefore you could have also retrieved the object as M104 in the MESSIER catalog or as NGC 4594 in the NGC catalog.

When the display returns to guide mode, press EXIT.

 

Example 3 – You want to locate the nearest Globular Cluster in Ophiuchus of Magnitude 15 or brighter. Assume the constellation is viewable.

Spin the DIAL in the top -level menu until you see -

 

MODE IDENTIFY

 

then press ENTER. Now spin the DIAL until you see -

 

FIND GLOBULAR CL

 

then press ENTER. Now spin the DIAL anti-clockwise until you see –

 

FAINTEST MAG +15

 

then press ENTER. Now spin the DIAL and make the first flashing character an ‘O’, then press ENTER. Now spin the DIAL and make the second character a ‘P’. The display should now show –

 

IN OPHIUCHUS

 

Press ENTER. The display should now show –

 

HORIZON MASK OFF

 

Press ENTER. Argo NavisTM then will briefly display the message -

 

SEARCHING

 

before showing you the name of the closest object. The object you find will probably be different, but by way of example, you might see –

 

TERZAN 5

FOUND

 

Pressing ENTER or spinning the DIAL one ‘click’ will put the unit into guide mode.

For example -

 

TERZAN 5

GUIDE 76®  25¯

 

After guiding to the object, press EXIT or spin the DIAL one ‘click’. Then press EXIT again.

 

Example 4 – You want to move the scope around and let Argo NavisTM tell you in ‘real-time’ what the closest object is.

Enter mode identify and spin the DIAL until you see -

 

FIND ANY OBJECT

 

then press ENTER. Now spin the DIAL until you see –

 

FAINTEST MAG ANY

 

then press ENTER. Now spin the DIAL and make the first flashing character an ‘A’, then press ENTER. Make the second character an ‘N’ then press ENTER. Now make the third character a ‘Y’. The display should now show –

 

IN ANY CONSTEL

 

 Press ENTER. Now spin the DIAL and make the first flashing digit a ‘3’ then press ENTER. Make the second digit a ‘6’ then press ENTER. Now make the third digit a ‘0’. The display should now show –

 

WITHIN 360°

 

Press ENTER. The display should now show –

 

HORIZON MASK OFF

 

Press ENTER. Argo NavisTM then will briefly display the message -

 

SEARCHING

 

before showing you the name of the closest object.

Now move your scope across the sky. Notice how quickly Argo NavisTM provides you with the name of the closest object. It is searching its entire database of tens of thousands of objects several times every second. The speed by which it does this should be testimony to its powerful processing ability.

Whenever the name of an object that looks interesting appears on the display, stop moving the scope. By pressing ENTER or spinning the DIAL one ‘click’ you can ‘lock-on’ to it as Argo NavisTM enters guide mode. Pressing EXIT or spinning the DIAL one ‘click’ will return you to the continual search mode.

Remember that while in guide mode you can press ENTER to get a scrolling description of the object.

 

Example 5 – You would like to tour every Galaxy of 13th Magnitude or brighter in Fornax.

Point your scope to the part of the sky from which you would like to begin the tour. The scope does not necessarily have to be pointed at Fornax.

Return to the top-level menu and spin the DIAL until you see -

 

MODE TOUR

 

then press ENTER. Now spin the DIAL until you see –

 

FIND GALAXY

 

then press ENTER. Now spin the dial until you see –

 

FAINTEST MAG 13

 

then press ENTER. Now spin the DIAL and make the first flashing character an ‘F’. The display should now show –

 

IN FORNAX

 

Press ENTER. The display should now show –

 

HORIZON MASK OFF

 

Press ENTER. Argo NavisTM then will briefly display the message -

 

SEARCHING

 

before showing you the name of the closest Galaxy in Fornax of 13th  Magnitude or brighter. Notice that you have automatically been put into guide mode. For example –

 

NGC 1049

GUIDE 14®  35¯

 

You can then move the scope and guide to the object. While in guide mode, if you spin the DIAL one ‘click’ clockwise,  Argo NavisTM will find you the next closest object, and so forth. When you reach the end of the tour, you will see the message –

 

NO MORE OBJECTS

 

You can even spin the DIAL anti-clockwise at any time and go backwards through the tour. While it is searching backwards, you will briefly see the message –

 

BACKTRACKING

 

At any time while in guide mode you can press ENTER to get a scrolling description. Remember by grabbing the DIAL you can stop the automatic scrolling and instead scroll manually.

 

That concludes this brief introductory run. Hopefully by now you might have got some feel for how the unit operates. Argo NavisTM has many more features than are mentioned here. As suggested earlier, you are encouraged to read the various reference pages in the Operating modes section of this manual to help give you further insight into its various capabilities.

 



Operating modes

The Argo NavisTM interface is designed as a set of menus. This section describes the purpose of each menu and how to use it. Examples are provided. Each menu is listed in alphabetical order, which provides for a handy reference.

Essentially there are two main sets of menus. There are the top-level mode menus and there are the setup menus. The setup menus are accessed via entering mode setup in the top-level menu.

Use the DIAL to select a menu. Use the ENTER button to enter the menu and the EXIT button to exit it.

 

The mode menus are –

 

·         MODE ALIGN

·         MODE ALIGN STAR

·         MODE AZ/ALT

·         MODE CATALOG

·         MODE ENCODER

·         MODE EQ TABLE

·         MODE FIX ALT REF

·         MODE IDENTIFY

·         MODE RA DEC

·         MODE SETUP

·         MODE SIDEREAL

·         MODE STATUS

·         MODE TIME

·         MODE TIMER

·         MODE TOUR


The setup menus are –

 

·         SETUP ALIGN PICK

·         SETUP ALT REF

·         SETUP ALT STEPS

·         SETUP ARCHIVE

·         SETUP ATLAS

·         SETUP AZ STEPS

·         SETUP BRIGHTNESS

·         SETUP CONTRAST

·         SETUP DATE/TIME

·         SETUP DEBUG

·         SETUP DEFAULTS

·         SETUP ENC TIMING

·         SETUP EQ TABLE

·         SETUP GOTO

·         SETUP GUIDE MODE

·         SETUP LCD HEATER

·         SETUP LOAD CAT

·         SETUP LOCATION

·         SETUP MOUNT

·         SETUP MNT ERRORS

·         SETUP REFRACTION

·         SETUP SCRATCH

·         SETUP SCROLL

·         SETUP SERIAL

 

 



 

MODE ALIGN


Function

mode align allows you to align Argo NavisTM on the ‘Current Object’. The ‘Current Object’ is the last object referenced in any of the following
modes –

·         MODE ALIGN STAR

·         MODE CATALOG

·         MODE IDENTIFY

·         MODE TOUR

 

Therefore, you can align Argo NavisTM on any object at any time, including during your initial alignment.

See mode align star for an alternative and convenient way of aligning from a list of 35 bright alignment stars.

 

Using MODE ALIGN

Enter mode align by spinning the DIAL in the top-level menu and pressing ENTER when you see –

 

MODE ALIGN

 

appear on the display. You will then be prompted with the message align followed by the name of the Current Object. When Argo NavisTM is first powered-on, the default Current Object is the first object from the first catalog.

Centre the Current Object in your eyepiece (not just the finder scope), then press ENTER. A status message will briefly appear on the bottom line of the display reporting the “warp factor for the alignment. See mode align star for a complete discussion of the WARP factor and alignment process.

 

Examples

You would like to align on Jupiter.

In the top level menu, spin the DIAL until you see –

 

MODE CATALOG

 

then press ENTER. Spin the DIAL until you see -

 

PLANETS/SUN

 

then press ENTER. Spin the DIAL until you see -

 

JUPITER

 

then press EXIT. Spin the DIAL anti-clockwise until you see –

 

MODE ALIGN

 

then press ENTER. The display should then show –

 

ALIGN JUPITER

 

Centre Jupiter in your eyepiece (not just the finder scope), then press ENTER.

A status message will briefly appear on the bottom line of the display reporting the “warp factor for the alignment.

The warp factor is the difference between the angular distance the telescope moved and the angular distance between two alignment stars or objects as a function of time.

The details of the warp factor message will differ depending upon the mount type you have set in setup mount, whether you have set auto adjust on or off in mode fix alt ref and whether this is the first or subsequent alignment. See mode align star for a full explanation.

For example, you might see –

 

ALIGN JUPITER

WARP=  -0.08

 

This indicates that you have aligned on Jupiter. In this case, the alignment was a second or subsequent alignment (see
mode align star for explanation). The WARP factor was –0.08 degrees, which is the difference between the computed angular positions of the alignment objects and the angular distance the telescope moved. In this case the alignment should probably give reasonable results since the warp factor was close to 0.00.

Note that if you have non-zero terms in the setup mnt errors/set error values/in use now submenu, rather than the word

 

WARP

 

appear, the display will show the word –

 

WARP

 

This acts a reminder that you have non-zero mount terms and an associated pointing model in place.
 See also

mode align star

mode catalog

mode fix alt ref

setup mount

setup mnt errors


 

MODE ALIGN STAR

 

 


Function

mode align star allows you to align Argo NavisTM quickly and conveniently on any of 35 bright naked-eye stars. Argo NavisTM can actually be aligned on any object (see mode align). However, the convenience of mode align star makes it compelling to use, particularly for your initial alignments.

 


Using MODE ALIGN STAR

Enter mode align star by spinning the DIAL in the top-level menu and pressing ENTER when you see –

 

MODE ALIGN STAR

 

appear on the display. Then spin the DIAL until the name of the star you wish to align on appears.

The alignment stars are listed in the following table -

 


Name

Constellation

Greek

RA J2000.0

Dec J2000.0

Mag

ACHERNAR

ERI

ALPHA

01:37:43

-57:14

0.5

ACRUX

CRU

ALPHA

12:26:36

-63:06

1.3

AL NAIR

GRU

ALPHA

22:08:15

-46:57

1.7

ALBIREO

CYG

BETA

19:30:43

+27:51

3.1

ALDEBARAN

TAU

ALPHA

04:35:55

+16:30

0.9

ALPHARD

HYA

ALPHA

09:27:35

-08:27

2.0

ALPHERATZ

AND

ALPHA

00:00:58

+29:05

2.1

ALTAIR

AQL

ALPHA

19:50:47

+08:44

0.8

ANTARES

SCO

ALPHA

16:29:24

-26:25

1.0

ARCTURUS

BOO

ALPHA

14:15:40

+19:14

0.0

BETELGEUSE

ORI

ALPHA

05:55:10

+07:24

0.4

CANOPUS

CAR

ALPHA

06:23:57

-52:42

-0.7

CAPELLA

AUR

ALPHA

05:16:41

+46:00

0.1

CASTOR

GEM

ALPHA

07:34:36

+31:53

1.6

DENEB

CYG

ALPHA

20:41:26

+45:17

1.3

DENEBOLA

LEO

BETA

11:49:03

+14:51

2.1

DUBHE

UMA

ALPHA

11:03:43

+61:45

1.8

FOMALHAUT

PSA

ALPHA

22:57:39

-29:37

1.2

HADAR

CEN

BETA

14:03:48

-60:22

0.6

KAUS AUSTRALIS

SGR

EPSILON

18:24:11

-34:22

1.9

MIMOSA

CRU

BETA

12:47:43

-59:41

1.3

MIRFAK

PER

ALPHA

03:34:19

+49:52

1.8

MIZAR

UMA

ZETA

13:23:55

+54:56

2.3

NAVI

CAS

GAMMA

00:56:42

+60:43

2.5

POLARIS

UMI

ALPHA

02:31:50

+89:16

2.0

POLLUX

GEM

BETA

07:45:20

+28:01

1.1

PROCYON

CMI

ALPHA

07:39:18

+05:21

0.4

RASALHAGUE

OPH

ALPHA

17:34:56

+12:34

2.1

REGULUS

LEO

ALPHA

10:08:22

+12:13

1.4

RIGEL

ORI

BETA

05:14:32

-08:12

0.1

RIGEL KENT

CEN

ALPHA

14:39:37

-60:38

0.0

SIRIUS

CMA

ALPHA

06:45:09

-16:43

-1.5

SPICA

VIR

ALPHA

13:25:11

-11:10

1.0

SUHAIL

VEL

LAMBDA

09:08:00

-43:26

2.2

VEGA

LYR

ALPHA

18:36:56

+38:47

0.0

 


Never use Polaris as an alignment star on an Equatorial mount and never use a star near the Zenith for alignment of an Az/Alt mount such as a Dobsonian.

For German Equatorial Mount users only - if you are in the Northern Hemisphere, place the tube on the West side of the mount. If you are in the Southern Hemisphere, place the tube on the East side of the mount. If you are going to do the first star alignment with the tube on the opposite side of the mount, go to setup alt steps and change the direction sense sign. Be sure to change it back when you want to do a first-star alignment on the original side of the mount.

Centre the chosen alignment star in your eyepiece (not just the finder scope), then press ENTER. A status message will briefly appear on the bottom line of the display reporting the “warp factor for the alignment.

The warp factor is the difference between the angular distance the telescope moved and the angular distance between two alignment stars or objects as a function of time.

When the ENTER button is pressed, Argo NavisTM refers to its internal catalogs and calculates the position of the alignment object in terms of its Azimuth and Altitude at that moment in time. Since it also keeps track of the movement of the encoders, it has all the information necessary to calculate the warp factor.

If you had selected fork exact align or gem exact align in the setup mount menu, then the warp factor will always be 0.00. For example, if you had selected to align such a mount using Rigel, a Magnitude 0.1 star in Orion, you would receive this message -

 

ALIGN RIGEL

WARP=  +0.00

 

For fork exact align or gem exact align mount settings where the mount is accurately polar-aligned, only one alignment star is necessary to align Argo NavisTM.

For altaz/dobsonian, fork rough align and gem rough align mount settings, two alignment stars and a fix alt ref (see
mode fix alt ref) step are necessary.

If you are performing the first
align star or align operation for a mount that requires two alignment stars, then the designation (1)’ will appear after the WARP factor to remind you that this was only the first alignment. For example –

 

ALIGN SIRIUS

WARP=  +2.32 (1)

 

If you are performing the second or subsequent align star or align operation for a mount that requires two alignment stars, then you should take special note of the warp factor when it appears. In general, you will want to achieve a warp factor as close to 0.0 as possible.

If you had set auto adjust off in mode fix alt ref then a perfect alignment would give you a warp factor of 0.00, though values in the range of +0.50 to
-0.50 should normally achieve an acceptable alignment. For example –

 

ALIGN VEGA

WARP=  -0.10

 

indicates that you have performed a second or subsequent alignment.  The alignment star was Vega. The WARP factor was 0.1 degrees, which is the difference between the computed angular positions of the alignment objects and the angular distance the telescope moved. In this case, the alignment should probably give reasonable results.

If you had set auto adjust on in
mode fix alt ref then you should always see a warp factor of 0.00 unless an ALT REF adjustment could not be computed (see mode fix alt ref). If an ALT REF adjustment could be automatically computed, the designation (a)’, for ‘Automatic’, will appear after the warp factor to remind you that auto adjust is on. For example –

 

ALIGN BETELGEUSE

WARP=  +0.00 (A)

 

indicates that you have performed a second or subsequent alignment. The alignment star was Betelgeuse and Argo NavisTM automatically computed the ALT REF adjustment.

When the automatic ALT REF adjustment cannot be computed, the designation ’(x)’ will appear after the WARP factor as a warning. For example –

 

ALIGN BETELGEUSE

WARP=  -94.66 (X)

indicates an alignment on Betelgeuse has failed because the ALT REF adjustment could not be computed. See mode fix alt ref for an explanation of the reasons the alignment may have failed.

Note that if you have non-zero terms in the setup mnt errors/set error values/in use now submenu, rather than the word

 

WARP

 

appear, the display will show the word –

 

WARP

 

This acts a reminder that you have non-zero mount terms and an associated pointing model in place.

If you perform a second or subsequent alignment and Argo NavisTM has failed to detect that the telescope has moved, the alignment will not be performed and a warning message will appear. For example –

 

ALIGN ALPHERATZ

SAME TELE POS ?

 

Indicates an alignment on the star Alpheratz has failed because the telescope did not appear to move. In this situation, you might want to check your encoder cable and connections.

 

Additional information, both introductory and advanced, that discusses many of the causes of pointing errors and how to diagnose them, can be found in the setup mnt errors section of this Manual.

 

Note: For German Equatorial Mount users only – your second alignment star can be sighted with the optical tube on either side of the mount.

 

See also

mode align star

mode align

mode fix alt ref

setup mount

setup mnt errors

 


 

MODE AZ ALT

 

 


Function

mode az alt allows you to determine the position of the telescope in an azimuth-altitude co-ordinate system. This mode assumes that you have performed a valid alignment, that the current date and time have been set in setup date/time and that your location, in particular your current latitude and longitude, have been set in setup location.

 

Using MODE AZ ALT

The azimuth values range from 0° to 360°, where north is 0° and east is 90°.

The altitude values range from -90° to +90°, with 90° at the zenith, -90° at the nadir and 0° at the horizon.

The angles displayed are shown in degrees and arc minutes.

Enter mode az alt by spinning the DIAL in the top-level menu and pressing ENTER when you see -

MODE AZ ALT

The display will show the telescope's azimuth on the left and the telescope's altitude on the right. If a valid alignment has not been performed, a scrolling warning message will be displayed, possibly similar to this one –

 

TWO SIGHTINGS ARE REQUIRED. FIX ALT REF MAY BE REQUIRED. WARNING – DISPLAYED VALUES MAY NOT BE VALID.

 

Otherwise the bottom line of the display shows the name of the constellation that the telescope is currently pointing towards. For example -

195°48’ +37°26’
CETUS

suggests the telescope is pointing southwest to 195°48' and is elevated to point 37°26' above the horizon.

Pressing ENTER again will briefly display the page number of the default atlas (see setup atlas) that covers the area of the sky the telescoping is pointing to -

 

195°48’ +37°26’

MSA=VOL I 262

 

In this example, Volume I page 262 of the Millennium Star AtlasTM.

To leave mode az alt, press EXIT.

 

See also

mode align

mode align star

mode ra dec

setup date/time

setup location



 


 

MODE CATALOG

 

 


Function

mode catalog allows you to look-up an object by name then to optionally guide to it and to also optionally retrieve more information about it. When an object is accessed in mode catalog it automatically becomes the Current Object. That means that it will appear as the alignment object when entering mode align.

Objects in the Argo NavisTM are grouped in a number of catalogs.
mode catalog allows you to browse the available catalogs and to either access a particular object in a particular catalog or to browse objects within the catalog.

 

Using MODE CATALOG

Enter mode catalog by spinning the DIAL in the top-level menu and pressing ENTER when you see –

 

MODE CATALOG

 

appear on the display. You will be prompted by a message such as –

 

BRIGHT STARS

 

where the words  BRIGHT STARS

 will be flashing.

 

By spinning the DIAL, you can cycle through the list of available catalogs. The catalogs are listed in alphabetical order.

The current catalogs are –

·         ASTEROIDS (assuming your Argo NavisTM has an asteroid catalog currently loaded)

·         BRIGHT STARS (a selection of stars to magnitude 6.5, particularly those with well-known historical names, such as BETELGEUSE and those with Bayer Greek alphabet or Flamsteed numbers. Names have constellation abbreviation first, then Bayer or Flamsteed identifier. For example, FOR ZETA for Zeta Fornax. They are ordered this way to make the catalog easier to browse)

·         COMETS (assuming your Argo NavisTM has a comet catalog currently loaded)

·         FROM PLANETARIUM  (consists of the single “FROM PLANETARIUM” object. When Argo NavisTM is interfaced via a serial port to an appropriate planetarium program and a GOTO command is issued from that program, the RA/Dec co-ordinates corresponding to that GOTO position and optionally the name of some associated object are transmitted to the “FROM PLANETARIUM” object. This then allows you to guide to the position that was sent from the planetarium program)

·         IC (non-stellar selections from the Index Catalogue)

·         MESSIER (the complete Messier Catalogue)

·         MISC BRIGHT NEB (miscellaneous bright nebulae, such as emission and reflection nebulae, that do not appear in the messier, ngc or ic catalogs)

·         MISC DARK NEBULA (miscellaneous dark nebulae)

·         MISC DOUBLE STAR (miscellaneous double stars that do not appear in the bright star catalog)

·         MISC GALAXIES (miscellaneous galaxies that do not appear in the messier, ngc or ic catalog, such as ESO, MCG, UGC and Local Group galaxies)

·         MISC GALAXY CLUS (miscellaneous galaxy clusters such as the Abell and Hickson clusters)

·         MISC GLOBULARS (miscellaneous globular clusters that do not appear in the messier, ngc or ic catalogs)

·         MISC OPEN CLUST (miscellaneous open clusters that do not appear in the messier, ngc or ic catalogs)

·         MISC PLANETARIES (miscellaneous planetary nebulae that do not appear in the messier, ngc or ic catalogs)

·         MISC VARIABLE ST (miscellaneous variable stars that do not appear in the bright star catalog)

·         NGC (the complete New General Catalogue, including all non-stellar, stellar and non-existent objects. Also includes ‘letter suffixed’ objects such as NGC 554A and NGC 554B and all objects that are also Messier objects)

·         PLANETS/MOON/SUN (in our solar system)

·         POPULAR DEEP SKY (a convenient cross reference to objects in the messier, ngc or ic catalogs that have popular names, such as ANDROMEDA GALAXY, GHOST OF JUPITER and TARANTULA NEBULA)

·         SATELLITES (artificial earth orbiting satellites - assuming your Argo NavisTM has a satellite catalog currently loaded)

·         SCRATCH (see setup scratch)

·         USER OBJECTS (assuming your Argo NavisTM has user defined objects currently loaded)

 

By way of example, say you are interested in the planetary nebula popularly known as the ‘Ghost of Jupiter’. Spin the DIAL and press ENTER when you see -

 

POPULAR DEEP SKY

You might be then presented with the message in the top line that reads -

 

47 TUCANAE

where the ‘4' will be flashing. By spinning the DIAL and pressing the ENTER button, you can use the Intelligent Editing SystemTM to enter the name of the object in which you are interested, in this example, Ghost of Jupiter. By spinning the DIAL clockwise (+), the symbol at the flashing cursor position will alphabetically increase. By spinning the DIAL anti-clockwise (-), the symbol will decrease. 'Wrapping' occurs when the 'maximum' symbol is displayed and the DIAL is turned clockwise or when the 'minimum' symbol is displayed and the DIAL is turned anti-clockwise.

Note: A symbol might be a number or letter or even a special character such as a '/', a '-' or even a space ' '. In general, Argo NavisTM treats special characters as alphabetically before numbers and numbers as alphabetically before letters. See the section on How Argo Navis orders its symbols for a reference table.

 

Spell out the name of the object by spinning the DIAL and pressing ENTER to select a character and advance the cursor to the next editable field. The Intelligent Editing SystemTM will only prompt you with valid names. A tip is to concentrate just on one letter at a time. In this example, spin the DIAL clockwise until the letter 'G' appears at the flashing cursor position.

The display might show something like

 

GEM CLUSTER

Now press ENTER to advance the cursor to the next editable field. In this case the display might continue to show

 

GEM CLUSTER

 

but now the 'E' in GEM will be flashing. Spin the DIAL clockwise until an 'H' appears at that place. The display might then show -

 

GHOST OF JUPITER

 

with the 'H" still flashing. Now press ENTER again. If a valid alignment has not been performed, you will see the following warning message -

 

GHOST OF JUPITER

NOT ALIGNED

 

In this case pressing ENTER again will give a further alignment warning message. If a valid alignment has been previously performed, Argo NavisTM will enter guide  mode.

 

Note :  As a special feature, if you select the PLANETS catalog, the planet of interest can be found by rotating the DIAL. The planets are listed in Solar System order and are spelt out in full. When the name of the planet of interest appears on the display, simply press ENTER to go to guide mode.

 

Continuing with our example, the display might read -

 

GHOST OF JUPITER

GUIDE 101®25¯ 

 

This means the telescope should be moved 101° in azimuth and 25° in altitude to locate The Ghost of Jupiter. The arrows represent a relative movement. For example, if the ® arrow is displayed, even though the arrow points to the right, whether one moves the telescope to the right or to the left is dependent on several factors according to your setup. If you wish to change the default direction sense of one or both arrows, you can do so by changing the settings in setup guide mode.

In any case, you should move the telescope in the direction that causes the angle to become smaller. As the telescope is moved, the display continually updates the angles and changes the direction arrows if the object is passed. When an angle less than 10° is displayed, the arrow will move to double as a decimal point. For example, 5¯3 means 5.3°.

Generally you might find it is easier to move the telescope in one axis at a time. When the telescope is at the correct position, you will see -

 

GHOST OF JUPITER

GUIDE 0.0 0.0

 

If a proper alignment has been performed, the object should appear within the field of view of a moderate power eyepiece (for example, one that gives a field of view of about 30 arc minutes). If objects do not appear consistently within the field of view, you might want to perform a re-alignment or review the section Factors that affect pointing accuracy.

 

Detailed object description

At any time during guide mode, if you press ENTER, a scrolling description of the object is given. Typical descriptions include the full name of the object, other popular names the object might be known by, what constellation the object is in, the size of the object, the visual magnitude of the object, its surface brightness, in the case of stars its spectral luminosity class, in the case of galaxies its abbreviated Hubble morphology, the object's Right Ascension and Declination, whether it is currently above or below the horizon and what volume and page of the default atlas the object would appear on (See setup atlas). For the Moon, you can determine its current phase and the local date and time of the next phases.

While the description is scrolling (to change the default scroll rate, see setup scroll), you can press EXIT or ENTER to have Argo NavisTM go back to guide mode or wait until the description has completed scrolling and Argo NavisTM will automatically return to guide mode. If you move the DIAL while the description is scrolling, manual scroll mode is entered.

Turning the DIAL clockwise scrolls the message forward for convenient reading at your leisure while turning the DIAL anti-clockwise scrolls the message in reverse. By pressing EXIT or ENTER while in manual scroll mode, Argo NavisTM will return to guide mode

 

Sequentially stepping through a catalog

While in guide mode, if you spin the DIAL clockwise (+), you can browse the next object in the currently selected catalog. Similarly if you rotate the DIAL anti-clockwise, you can browse the previous object.

 

Below horizon indication

Whenever you are about to locate an object you may want to automatically determine if it is below your local horizon or not.

To do so, ensure that your time zone, date and local time is correctly set in setup date/time, that your latitude and longitude are correctly set in setup location and that in setup guide mode you have set guide below horz to h indicator=on.

For example, if the display showed -

 

GRUS QUARTET

GUIDE 19®132¯H

 

the h symbol at the end of the second line indicates that the grus quartet is currently beneath your local horizon.

 

 

Examples

Example 1 - You want to observe the Ghost of Jupiter.

Spin the DIAL until you see -

 

MODE CATALOG

 

then press ENTER. Spin the DIAL until you see -

 

POPULAR DEEP SKY

 

then press ENTER.

 

Use the Intelligent Editing SystemTM to enter the name of GHOST OF JUPITER and then press ENTER.

The display might then show -

 

GHOST OF JUPITER
GUIDE 5®0 7¯3

 

Move the telescope in both axes until the display reads -

 

GHOST OF JUPITER
GUIDE 0.0 0.0

 

Pressing ENTER again will display the following scrolling information about the object.

 

GHOST OF JUPITER ALSO KNOWN AS NGC 3242 PLANETARY NEBULA IN HYDRA SIZE=25" MAG=7.8 GHOST OF JUPITER. BLUE GREEN. BRIGHT INNER DISK & FAINT HALO RA=10:24:46 DEC=-18°38'34" J2000.0 ABOVE HORIZON MSA=VOL II 851

 

While the text is scrolling, you can enter manual scroll mode by moving the DIAL.

Note: Had you known that the Ghost of Jupiter is also known as NGC 3242, you might well have accessed it via the NGC catalog.

 

Note that when sample mode is on, in the setup mnt err/acquire data submenu, rather than a scrolling description immediately appearing, a new submenu appears.

In this case, by spinning the DIAL a detent ‘click’ at a time, the bottom line of the display can be alternated as follows –

 

·         DESCRIPTION

·         SAMPLE MNT ERROR

 

If you want to view the description of the object, spin the DIAL until the word DESCRIPTION appears and then press ENTER. If you want to sample the position of an object as part of a pointing test, spin the DIAL until the words SAMPLE MNT ERROR appears and then press ENTER (See setup mnt errors for details).

 

Pressing EXIT will return you to guide mode -

 

GHOST OF JUPITER
GUIDE 0.0 0.0

 

Pressing EXIT again will return you to the top-level menu -

 

MODE CATALOG

 

 

Example 2 - You want to align on MARS.

 

Spin the DIAL until you see –

 

MODE CATALOG

 

then press ENTER. Spin the DIAL until you see -

 

PLANETS/SUN

 

then press ENTER.

Spin the DIAL until you see -

 

MARS

Press EXIT. Mars is now the Current Object.

Spin the DIAL counter-clockwise until the display reads –

 

MODE ALIGN

then press ENTER.

The display should show -

 

ALIGN MARS

Centre Mars in the eyepiece and press ENTER to perform the alignment.

 

Example 3 - You want to determine the current Moon phase and when the next New Moon will be.

Spin the DIAL until you see -

 

MODE CATALOG

 

then press ENTER. Spin the DIAL until you see -

 

PLANETS/MOON/SUN

 

then press ENTER.

Spin the DIAL until you see –

 

MOON

Press ENTER and then press ENTER again. A scrolling description will appear. Whilst the text is scrolling, you can enter manual scroll mode by moving the DIAL.

 

MOON CURRENTLY IN VIRGO MAG=-11.7 DIA=30.4’ ILLUM=38.6% PHASE=LAST QUARTER NEXT LAST QTR=10-DEC-2017 18:51 LOCAL NEXT NEW MOON=18-DEC-2017 17:31 LOCAL NEXT FIRST QUARTER=26-DEC-2017 20:20 LOCAL NEXT FULL MOON=2-JAN-2018 13:24 LOCAL DIST=392462KM RA=12:16:55 DEC=+02°48’00” J2000.0 BELOW HORIZON HB=E12,C48

 

 From the description the Moon phase is currently close to Last Quarter and the next New Moon will be on 18 DEC 2017 at 17:31 local time.

 

Example 4 – Whenever you are about to locate an object, you want to automatically determine if it is below your local horizon or not.

Ensure your time zone, date and local time is correctly set in setup date/time, that your latitude and longitude are correctly set in setup location and that in setup guide mode you have set guide below horz to h indicator=on.

For example, if the display showed -

 

TARANTULA NEBULA

GUIDE 169®108¯H

 

the h symbol at the end of the second line indicates that the tarantula nebula is currently beneath your local horizon.

 

See also

mode align

mode align star

setup date/time

setup location

setup guide mode

Catalogs

How Argo Navis orders its symbols