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>TOOLS FOR ASTRONOMY

             DAVID CHANDLER CO.-- SOFTWARE, SLIDES, AND PUBLICATIONS
      (All items authored and published by David Chandler except as noted)

 DEEP SPACE 3-D, Ver 2.0 -- Program Disk, Data Disk, Small 3-D Viewer
     Single User Registration                          $  59   _____   ______
     Site Registration (Per building)                  $ 120   _____   ______
 LARGE TABLE-TOP 3-D VIEWER KIT                        $  35   _____   ______
     (For viewing pairs of 8-1/2 x 11 printouts in stereo)
 COMET WATCH--A newsletter for announcements of new comet discoveries, giving
     orbital elements that can be used with DEEP SPACE 3-D.  15 issues per
     volume, "Vol 0" gives extra background information and lots of data to get
     started. (All subscriptions begin and end at volume boundaries to simplify
     bookkeeping.)
                                             Vol 0   $ 10 ea   _____   ______
    _____ Volumes starting with the current Volume   $ 10 ea   _____   ______
   Small 3-D viewer, when ordered with Comet Watch   $  3 ea   _____   ______
-              (Overseas Subscriptions: $ 15, viewer $  4)     _____   ______

 ------------------------------------------------------------------------------
 |                         (** REGISTERED USERS ONLY **)                      |
 |    Additional Star Database Files: SST05-SST77, 15 disks, 248,709 Stars    |
 | Circle Disk #'s: 1   2   3   4   5   6   7   8   9  10  11  12  13  14  15 |
 |                                                                            |
 | 1 or more, $10 ea / 5 or more, $8 ea / 10 or more, $7 ea   AMOUNT:  ______ |
 |                                                                            |
 |  Also: Orbital elements for over 1100 comets dating back to 240 BC, based  |
 |  on Brian Marsden's "Catalog of Cometary Orbits" (and more)  $ 15   ______ |
 ------------------------------------------------------------------------------

 DEEP SPACE 3-D, Ver 2.0 (Unregistered Trial Copy--Disks Only)
     (With $15 coupon toward registration price)       $  15   _____   ______
 SMALL 3-D VIEWER  (by Taylor-Merchant Co.)            $   5   _____   ______
 PLANETS IN THE CLASSROOM (Not Shareware) -- A program for understanding
     planetary motion, specifically designed for teachers, but of interest to
     amateur astronomers as well.  Comes with a manual of classroom exercises
     appropriate for various levels from elementary through college.
                          IBM _____  APPLE II _____    $  39   _____   ______
-    (Apple version implemented by Michael Lovekin.)

 ** THE NIGHT SKY ** / A specially designed low distortion "Star Wheel" for
 anyone who really wants to get to know the sky.  This practical, take-it-out-
 and-use-it star finder is the real backbone of our product line.  Over 1/4
 million copies are in circulation.  Astronomy educators are its most vocal
 fans:
   "The Night Sky is not just another planisphere.  I think The Night Sky is
 the finest and easiest to use star finding aid in existence."
  -- Jack Horkheimer, T.V.'s "Star Hustler", and Planetarium Director at the
     Miami Museum of Science.                         $ 5.95   _____   ______
                              Latitude or nearest large city   ______________
-    (Teachers: Ask for "Sample Classroom Exercises using The Night Sky")
+
 EXPLORING THE NIGHT SKY WITH BINOCULARS -- (Illustrated by Don Davis)
 A written companion to THE NIGHT SKY that leads the beginner from "naked eye"
 astronomy to the ideal "first telescope": a simple pair of binoculars.  It
 covers both what to see and the significance of what is seen.  This book was
 written with adults in mind, but it received honorable mention in the Older
 Children's Division of the New York Academy of Sciences Children's Science
 Book Awards.
   "...the best short introduction to astronomy ever written." --Doug McCarty,
 Planetarium Director, Mt. Hood Community College.
   "From the creator of what I consider to be the best planisphere available
 (The Night Sky), comes Exploring the Night Sky with Binoculars, a companion to
 that star dial.  Taken together, the two items--plus a pair of binoculars--
 constitute the best introduction to observational astronomy you could ask
 for." --John Mood, Astronomy Magazine.               $ 5.95   _____   ______
-             (Star Dial and Book ordered together)     $ 10   _____   ______

 DON DAVIS ARTWORK -- Slides of the paintings of one of the world's greatest
 space artists.  These slides are like photographs from points in time and
 space inaccessible to the camera.  They come fully annotated to interpret
 the wealth of subtle, accurate detail found in each painting.  (For more
 background on Don Davis, see the June 1985 issue of Sky and Telescope.)

   The Moon and its Formation (21 slides) -- A classic time lapse sequence
   showing the formation of the moon from its early accretion to the present
   day.                                                 $ 21   _____   ______

   The Earth (16 slides) -- The earth through time, continental drift, impacts
   from space, theories of dinosaur extinction.         $ 16   _____   ______

   Eclipses (12 slides) -- Lunar and solar eclipse phenomena as seen from the
-  earth, space, and the surface of the moon.           $ 12   _____   ______

   The Terrestrial Planets (18 slides) -- Mercury, Venus, and Mars, with
   emphasis on Mars and the Viking missions.            $ 18   _____   ______

   The Outer Solar System (36 slides) -- The gas giants, their moons, their
   rings, the solar system as seen from Pluto and the Pioneer X spacecraft as
   it leaves the solar system.                          $ 36   _____   ______

   Beyond the Solar System (10 slides) -- The Orion Nebula, the Milky Way, a
   time sequence of Hercules X-1, and the gravitational lens effect of a black
   hole.                                                $ 10   _____   ______

   All six sets ordered simultaneously (113 slides) $ 107.35   _____   ______

  (For reproduction rights or arrangements for commercial use of slides, write
- to Don Davis, c/o Hansen Planetarium, Salt Lake City, UT.)
\ ---------------------------------------------------------------------------
                                       6.75% Sales Tax (in CA only)    ______
                    $3 Domestic Shipping Charge on All Slide Orders    ______
   ** Overseas **      Large 3-D Viewer: (Air) $ 35, (Surface) $ 13    ______
   ** Overseas **  All other items, add: (Air) $  5, (Surface) $  2    ______
  (Checks must be payable in US Dollars drawn on US banks)    TOTAL:   ______
    (Domestic shipping will be added on all invoices if not paid in advance)

 Name_________________________________________________________

 Address______________________________________________________

 City___________________________________State______Zip________
>A SAGA IN THREE PARTS
                                    PART I
      A new comet is discovered!  It is faint now, but it is expected to 
 brighten almost to naked-eye visibility (about 6th magnitude) in a few weeks.  
 The newspapers won't carry stories about this one, but you know about it 
 within a week of its discovery because you subscribe to COMET WATCH.  
      You have had bad luck with comets in the past.  You tried to find 
 Halley's Comet but couldn't find it in your brand new marketed-for-the-
 occasion telescope.  The bottom line is you couldn't find your way around the 
 sky and didn't know exactly where to point the thing...but this time things 
 will be different!  You have all the right tools: a sturdy star dial that you 
 are using nightly to learn the constellations one by one, a nice little book 
 that made you realize the value of those binoculars you had hidden up in a 
 closet while you were struggling with your new telescope, and DEEP SPACE 3-D, 
 the most versatile comet crunching computer program available. 
      Back to our story.  COMET WATCH arrives in the mail.  You type in the six 
 magic numbers that specify the comet's orbit.  Within minutes you have on the 
 screen an ephemeris for the next two months.  "Ephemeris"...you just learned 
 the word, but it has a nice ring to it.  It means lots of numbers!  You go on.  
 Within minutes you have printed out a large-scale finder chart in "star atlas 
 mode" which you can use to spot the faint smudge with your binoculars, and in 
-turn guide your telescope to its target... 
      But that's not all.  You run What's Up for the current date and look at 
 the rise and set times for the comet.  You see that the comet rises at 4am, so 
 you run What's Up again, this time for an early morning hour.  You do another 
 ephemeris, this one correlated with the current What's Up settings.  You plot 
 an all sky map and see two paths for the comet: one showing its path relative 
 to the constellations, just what you had before, and the other one showing its 
 path relative to the horizons.  These paths gradually separate, since the star 
 positions are for one particular night, but the comet is shown for several 
 weeks, during which time the sky will have rotated considerably.  You use the 
 cursor to identify the dates when the comet will be highest above the horizon 
 and are pleased to see it will be well placed when it is at its brightest. 
      You run yet another ephemeris, this one not for "finding", but for 
 "understanding".  You plot out the whole orbit on the screen and see how the 
 comet zips past the earth's orbit in its brief encounter with the sun before 
 its slow return to the outer fringes of the solar system.  You put the cursor 
 on the screen and use the <HOME> key option to step along the orbit, matching 
 the earth's position with the comet's position day for day.  You plot out the 
 orbit in 3-D to help visualize the orientation of the comet's orbit in space.  
 It is apparent that this comet's orbit is highly inclined to the plane of the 
 solar system.  The comet will loop up and over the earth, causing it to move 
 far to the north in the sky then disappear below the southern horizon.  Not 
-only are you confident of finding this comet, you have come to know it well. 
                                     PART II
      You are a teacher planning a sky observation night for your students. You 
 want to find a date when the moon is up for viewing in the evening sky but not 
 so close to full that it will drown out everything else.  You want your 
 students to get home at a reasonable hour, but you want to stay late enough so 
 it will be fully dark.  You would like your students to see the rings of 
 Saturn or the moons of Jupiter in a telescope, but you realize these planets 
 are not always out in the evening sky.  How can you plan for a successful 
 session in time to announce it to parents a month or more in advance? 
      The What's Up option is the place you start.  You enter a rough target 
 date and your observing site.  You immediately see the dates of all the new 
 moons thoughout the year and all of the moon phases in your target month.  You 
 pick a date near first quarter for a well placed evening moon.  (Craters show 
 up best at first quarter because they cast long shadows then.)  The default 
 observing time is the end of evening twilight, which looks OK to you, so you 
 accept it.  You choose the ALTER DATE option to zero in on the day best suited 
 for your event.  You print out the information screen for your own reference. 
 With the date and time selected, you go on to check out the rise and set times 
 of the moon and planets.  Returning to the main menu you run a full-sky star 
 map for the event, limited to 3rd magnitude stars (since you know that's all 
 that will be visible from town anyway).  You print it out, duplicate it, you 
-are ready to go.
                                    PART III
      You are an avid amateur astronomer, out on a mountain top long past most 
 people's bed time.  You run across a "faint fuzzy" in your telescope that 
 isn't on your star atlas.  You do a careful sketch of the field stars to get a 
 fix on its position, estimate its magnitude, and watch it for a half hour or 
 so to verify that it drifts slowly past the background stars.  It does!  You 
 have a comet!  Anticipating immortality (for your last name at least) you risk 
 life and limb rushing back down the winding mountain road...but before placing 
 a telegram to Cambridge, MA, you decide to check What's Up first.  
 
      You subscribe to COMET WATCH, so you have maintained a file of all the 
 comets that have come by in the last few years.  You have copied the ones 
 currently visible to a smaller file for easy access.  You run What's Up to get 
 a listing of positions, estimated magnitudes, and rise and set times.  Just 
 for good measure you run it for the whole file so nothing will slip by.  You 
 don't like looking at long lists of numbers, so you select all the comets for 
 inclusion on the star chart, return to the main menu and generate a star chart 
 for the current day and time.  You choose the function key for "Planets etc." 
 and every comet in the file shows up on the screen (most of them far too faint 
 to be visible).  You immediately notice a comet close to where you found 
 yours.  You put the cursor on it to identify it and go back to the What's Up 
-option again to take a closer look... 
      It becomes clear that the comet you discovered (you really discovered 
 it!) was also discovered several months earlier by someone named Liller.  In 
 fact you had looked at it back then when it was much brighter and had a nice 
 tail, but it was in a totally different part of the sky.  It had dimmed down 
 so much that you had removed it from your current comet file (CURRENT.CFL), 
 but had the good sense to keep it in your backup comet file (RECENT.CFL).  
 You're disappointed, but you realize that your thorough search has saved you 
 from the embarrassment of a false alarm and the expense of a needless 
 telegram.  Still you realize that your comet is out there waiting for 
 you...but that's for another day. 
                                      .....
 
 (That's how it might have been.  The truth of the matter is I didn't have 
 What's Up at the time.  I did have Version 1.3 of DEEP SPACE up and running, 
 and I did have Comet Liller on file!  If I had taken the time I could have run 
 ephemerides for all the comets in the file and found that Comet Liller was 
 still bright enough to be seen and right where it should have been...but that 
 was too time consuming, so I just checked a few likely candidates.  I sent the 
 telegram and later swallowed hard when I discovered my error.  I decided then 
 and there to add a new option to the program.  That's why you and I have the 
 handy What's Up option today.  I have written this program for me.  If you 
 like astronomy like I like astronomy, you might find it nice for you too.) 
>THE DISTRIBUTION DISKS
 
 DEEP SPACE 3-D, Version 2.0 comes on three floppy disks.  We encourage you to 
 pass around good, clean copies of the unaltered disk set.  Please do not 
 delete any files.  

   The PROGRAM disk should contain: 

   DS3D.EXE, DS3D.OVR -- The main program and overlay files
 
   {CGA, HERC, EGAVGA}.BGI -- Video drivers
 
   README.DOC, INSTALL.BAT, $$.BAT, $$$.BAT -- Installation Files
   (These are used only when transfering files to a hard drive.)

   DS3D.BAT -- Batch file for use on a hard drive to transfer you to the DS3D 
   subdirectory and run the program.

 If DSCONFIG.FIL is present, the disks have been used previously and contain 
 someone else's configuration data.  Delete this file or choose the CHANGE 
 CONFIGURATION SETTINGS option at the main menu when you start the program. 
-
 The DS SUPPLEMENT disk should contain:

   {PLCRUNCH, CONLINE, NAMENUM}.DAT -- External files needed by the program
 
   CONVERT.EXE -- A separate program to convert among Version 1.3 comet files, 
      Version 2.0 comet files, and Text files.
 
   RECENT.CFL -- Comet orbital elements (starter set)
      Comet files will expand as you add data on more comets.  (You can keep up 
      to date on your comet files by subscribing to Comet Watch.) 

   TEXT.TXT -- The text file you are reading at this very moment.

   SST01 -- The first of six star data files distrubuted with the core 
      program.
-
 The STAR DATA #0 disk should contain:
  
   SST{02, 03, 04, 05, 06} -- The basic star data (expandable to SST77)
      (Only the first six SST files are part of the Shareware package.  If you 
      have obtained more than these six SST files without registering your 
      program and purchasing them directly, you are eating forbidden fruit at 
      our expense.  Please either register or delete the additional files.) 
\
\
-
 The hard disk installation program INSTALL.BAT creates a directory called 
 \DS3D, and two sub directories called DSDATA and DSFILES.  
 
 --All of the files on the DEEP SPACE 3-D disk and most of the files on DS 
   SUPPLEMENT are copied to the \DS3D directory.  
 --The SST files are copied to the DSDATA sub directory
 --The CONVERT.EXE program and the comet data file, RECENT.CFL, are copied to 
   the DSFILES subdirectory. 
 --The DS3D.BAT file is copied to the root directory.

 These directories could be renamed or two or more of them could be combined, 
 but the file groupings must remain intact for the program to access them 
 properly. 

>STARTUP OPTIONS
                                Startup Options

      If you have obtained clean copies of the distribution disks, you were 
 led through the configuration procedures at the beginning of the program.  
 You can alter your choices at any time by selecting the CHANGE DEFAULT 
 SETTINGS option at the Main Menu.  If the file path options or the video 
 display options are not set properly for your system the program will most 
 likely crash.  Other choices are more benign, but important for the user. 
      
      The first item on the configuration agenda is to specify the type of 
 video card in your machine.  The issue is the video card, not the monitor. You 
 may have a monochrome monitor with a CGA video card.  The program will attempt 
 to detect which card is present.  Under normal conditions you should be able 
 to accept the default selection.  This option is provided to override the 
 program's choice if it is unable to detect the correct card or if more than 
 one video card is present. 

      If you have something other than a Hercules display, your next choice is 
 the combination of colors to use.  Try the function keys as indicated to see 
 the range of possibilities and find a combination that is easily readable. 
-
      Next, give the names of the locations of the various groups of files 
 indicated.  If they are on floppy disks, give the drive letters.  Remember, 
 the main program files (DS.EXE and DS.OVR) must be continuously present on 
 the default drive.  The remaining can be anywhere on the system, or swapped 
 in and out at the program prompts if they are on floppy disks.  Even if the 
 main program is on a hard disk it is possible to use floppies for some of the 
 remaining files. 

      On the next page, specify the number of SST (Star data) files you are 
 using.  You should have six with the original disks and registered users may 
 purchase up to SST77. 
-
      Finally, there are two screens that have to do with your location.  You 
 may describe a primary and a secondary observing site.  A third site may be 
 defined "on the run" while running various options in the main program.  It 
 too will be stored until it is redefined.  
 
      Look on a large scale atlas at a library to find the latitude and 
 longidude of your observing site as accurately as possible.  Take a stab at 
 your altitude.  The accuracy here is not critical for most purposes.

      The name of your time zone is for printout purposes only.  The number of 
 the time zone is more critical.  A partial table is provided to help determine 
 the correct number.  Daylight time shifts U.S. observers one hour closer to 
 Greenwich (subtract one hour), and Asian observers one hour farther from 
 Greenwich (add one hour).

>DEFAULTS
                                    Defaults

      How do you make a program simple enough for a beginner and at the same 
 time powerful enough to satisfy an expert?  One way is to allow lots of 
 choices for the experts, even regarding picky details, but to suggest an 
 answer to every question that at least makes sense.  A "default" is computer 
 jargon for those pre-selected answers provided by the program.  DEEP SPACE 3-D 
 has default for just about everything!  This makes it easy to explore areas 
 you may not understand very well at first.  If you come to a question you 
 don't care about or don't understand, just choose the default and keep going.  
 The more you learn about astronomy, the more you will appreciate having 
 control over all the picky details.
      To choose a default answer, simply type the <ENTER> key.  You will find 
 that you can go through almost the entire program simply hitting the <ENTER> 
 key, and still get something of interest.  If you come to a whole page of 
 questions and like the looks of all the default answers, simply jump to the 
 bottom of the page with the <PgDn> key and keep going.  As you get more 
 comfortable with the program and read up more about astronomy, you will find 
 the program's capabilities will keep up with your growth along the way.
>DATA ENTRY
                                   Data Entry
 
     Data is entered either by making a selecting with a scroll bar or typing 
 data directly into input boxes.  

     To use the scroll bar, move up or down with the arrow keys, page up or 
 down with the PgUp and PgDn keys, go all the way to the beginning or end of a 
 list with the Home or End keys.  You can also select entries by their first 
 letter.  The cursor will cycle through all the entries having the same 
 starting letter.

     When entering data into the input boxes, most single character entries do 
 not require the use of the enter key.  Simply press the appropriate key.  To 
 allow you to recover from accidental keystrokes, there is usually an entry at 
 the bottom of a page to confirm the earier entries on that page.

     When editing an existing entry, if the first key typed is a normal 
 character, the entry will be erased under the assumption that you want to 
 retype the whole entry.  If you want to edit the entry without destroying 
 what is already there, make the first keystroke with a Home, End, or Arrow 
 key.  After destroying a few entries you will get used to it.
>WHAT'S UP: SUMMARY PAGE
                            What's Up: Summary Page

     The What's up option is a handy grab-bag of features for anyone who 
 actively observes the sky.  After specifying a target date you are given 
 information that you may want to use to refine your choice of date or narrow 
 in on a time most suitable to your observing needs. 

     The sun and moon both cast a lot of light and can adversely affect 
 observations of other fainter objects.  New Moon equals No Moon.  The time of 
 New Moon (plus or minus a few days) is traditionally the best time of the 
 month for astronomy club star parties.  First quarter moon will be overhead 
 in the evening sky, setting around midnight, and third quarter moon will not 
 rise until near midnight.  First quarter moon is a good time for public 
 viewing since the moon itself is a prime telescopic subject for the general 
 public.  First quarter is also good because the craters cast long shadows 
 along the terminator (the moon's "twilight zone"). 

     Sunrise and sunset are also important.  Times vary considerably 
 throughout the year, especially at higher latitudes.  Astronomical twilight 
 is defined as the time when the sun is 18 degrees below the horizon.  This is 
 the time when the sky is generally considered dark for astronomical purposes.
>WHAT'S UP: PLANETS, ETC
                            What's Up: Planets, Etc.
 
     The Planets page of the What's Up option gives a wealth of information 
 for anyone who wants to read it.  The other option is to let the computer 
 digest the information and display it visually on a map of the day and time.  
 In summary the column headings mean the following:
   
   R.A.       --Right Ascension: angle in hours, not degrees, measured 
                eastward along the equator from the Vernal Equinox.
   Dec        --Declination: angle above or below the celestial equator 
                measured in degrees.
   Long       --Ecliptic Longitude: angle in degrees measured eastward along 
                the ecliptic instead of the equator.
   Lat        --Ecliptic Latitude: angle in degrees above or below the 
                ecliptic.
   Elong      --Elongation: the angle of the planet from the sun as seen from 
                the earth.
-
 
 The remaining categories are rise and set and related times.  Besides rise 
 and set times there are two other categories: 
 
 20 deg rise/set: time of rise or set at a hypothetical "smog line" 20 degrees 
 above the horizon.  Even if there is no smog, at 20 degrees above the horizon 
 you are looking through 3 times as much atmosphere as directly overhead.

 Transit: time when the planet crosses the local meridian (the local meridian 
 being the north-south line passing directly overhead).

 If a planet never rises, the rise and set times are marked:   -----
 If a planet never sets, the rise and set times are marked:    +++++
 (Similarly if it never crosses the 20 degree altitude mark)
 
 The time of transit is indicated even if the planet is below the horizon at 
 that time.
>WHAT'S UP: COMETS
                               What's Up: Comets
 
     You may be able to tell this program is heavy on comets!  Comets are 
 interesting observational targets, although beginners often have difficulty 
 locating them.  Most require a telescope or at least binoculars to observe.  
 The comet ephemeris option follows a single comet over an extended period of 
 time.  The What's Up comet section, on the other hand, is a time cross 
 section.  It shows where any desired number of comets are at a single time.  
 Usually not more than two or three comets are actually bright enough to see 
 at one time, but the others are still out there, however, and may be plotted.  
 This is especially useful if you want to avoid mistaking a known comet for a 
 new discovery (cf. SAGA, Part III). 

     The comet option shows R.A., Dec., Elongation, rise, set, 20-deg rise 
 and set, and transit times (see planet page for descriptions of these).  Also 
 if the appropriate information is available in the file, an estimated 
 magnitude is given.  These estimates are rarely accurate, but they may 
 indicate whether a given comet is conceivably visible at a given time.
-
     Finally, you are given the opportunity to "select" any number of comets.  
 If a comet is selected, it is put on a list with the planets to be displayed 
 on the day and time star map.  For selection purposes you have several 
 options:

     Y: Select a given comet
     N: Reject a given comet
     S: Select all of the remaining comets
     R: Reject all of the remaining comets (but still scroll through them)
 <ESC>: Keep what has been selected so far, and quit.

 If you type S or R, you may interrupt the scrolling at any point and revise 
 your selections from that point onward.
>COMET ELEMENTS
                                 Comet Elements

     You can enter the orbital elements for a comet in the Comet Ephemeris 
 option.  Orbital elements are six numbers that describe a comet orbit's size, 
 shape, orientation in space, and time of closest approach to the sun.  They 
 have strange names, but you don't have to know anything about them to be able 
 to plug them into Deep Space 3-D.  If you subscribe to Comet Watch or get the 
 IAU circulars directly, simply put the right numbers in the right slots and 
 let the computer go at it.  Deep Space 3-D prints out the numerical data and 
 then allows you to display it in a variety of ways.

     The knotty problem has been how to obtain the elements.  This is not the 
 kind of thing you could get from monthly astronomy magazines.  The news is of 
 the fast breaking variety.  You could subscribe to the IAU Circulars 
 directly, or rely on your local planetarium for information, but now you can 
 get elements fast, directly from David Chandler Co. in our new newsletter 
 service: COMET WATCH.  See the TOOLS FOR ASTRONOMY heading for information on 
 how to subscribe. 
 
-The six magic numbers are as follows: 
 
                                Orbital Elements

 T     : Time of perihelion passage--when the comet is closest to the sun
 e     : Eccentricity--a measure of the elongation of the orbit.  For a 
         circle, e=0.  For a parabola, e=1.  Above 1 the orbit is a hyperbola.
 q     : Perihelion distance--closest approach to the sun
 PERI  : Argument of perihelion--measures the orientation of a comet's orbit 
         within its own orbital plane.
 NODE  : Longitude of the Ascending Node--locates where the comet's orbit 
         crosses the ecliptic plane.
 i     : Inclination--the angle bewteen the orbital planes of the earth and 
         comet. 
 
 These are published in IAU Circulars by the Center for Astronomical Telegrams 
 after a new comet has been discovered and tracked for several days.  Refined 
 elements are typically published after a longer period of observation.

>COMET FILES
                                  Comet Files

     If your interest in comets is purely observational, you can delete most 
 long period comets after they have faded.  Most will never return in your 
 lifetime.  However, for other aspects of comet study you may want to collect 
 orbital data to compare comets even after they are long gone.  One of the 
 optional disks available to registered users has data on over 1100 comets 
 dating back to the first confirmed sighting of Comet Halley in 240 BC (which 
 astronomers refer to as the year -239: Astronomers have a zero year; 
 historians don't!) 

     In any case, if you collect large amounts of orbital data it can best be 
 kept in multiple files.  The RECENT.CFL file is on the distribution disk by 
 itself, but another convenient file to create might be called CURRENT.CFL, 
 for only the currently visible comets.  

     To start a new file with fresh data, choose the Ephemeris Option at the 
 Main Menu.  When the existing comet files are shown, type <ESC> to start a 
 new file, and type in the new file name when asked.  You will then be 
 presented with the data entry form where new elements can be typed in.
-
     Instead of entering fresh data into the new file, data can be copied to a 
 new file or between existing files.  To do this, select a comet in an 
 existing file, and choose the Copy option shown at the bottom of the page 
 when its elements are displayed.  A menu of existing comet files will be 
 shown allowing you to select which file to copy it to.  If you want to start 
 a new file, type <ESC> to enter the new file name.

     Another option at the same point where the copy option is offered, is to 
 delete a comet.  You may well want to enter new comet data in CURRENT.CFL, 
 then copy it to RECENT.CFL and delete it from CURRENT.CFL when it is no 
 longer easily visible.

     The program CONVERT.EXE is a separate program from DEEP SPACE 3-D which 
 must be in the same subdirectory as the files it is to operate on (by 
 default, \ds3d\dsfiles, if you have a hard disk).  It will convert .CFL files 
 to or from the old Ver. 1.3 .DAT files, and also to or from ASCII .TXT files 
 that can be read, edited, or organized with a text editor or word processor.  
 If text files are to be converted back to .CFL form, they must be in pure 
 ASCII and follow the pattern of the text files produced by CONVERT.EXE.

>DAY AND TIME OPTIONS
                              Day and Time Options

     You can enter the starting day and time and range of dates for a comet 
 ephemeris in several ways, depending on the purposes you have in mind.  If 
 you want the program to display a comet orbit in relation to the earth's 
 orbit, choose the "A" option.  This allows you to select the calculation 
 interval and number of calculations, and the program chooses the starting 
 date to be symmetric about perihelion.  
 
     If the comet has a relatively short period you will be asked if you want 
 to compute positions for an entire orbit.  If you intend to display the 
 comet on the screen, there is room in the allocated memory space for 500 
 points, counting the comet head, comet tail, sun, earth, and any other 
 planet or comet positions that might be included.  Based on this space, the 
 program will proposed an interval and a number of positions to close the 
 orbit.  Look at the proposal and decide if it will be satisfactory for your 
 purposes.  Remember, comets move very quickly near the sun and very slowly 
 far from the sun, so the jumps can get to be quite large if the interval is 
 too long.  If the interval is 10 to 30 days, the results will usually look 
 reasonably good.  If the interval needed to get a complete orbit exceeds a 
 year, the option is not even offered. 
-
     Day-and-Time star maps are for a particular day and time, so comet 
 ephemeris calculations must be coordinated with this data to be meaningfull.  
 This is done automatically when you choose option "B".  Option B ephimerides 
 are linked to particular What's Up computations.  All you have to do is 
 specify the computation interval and number of computations.

     The C option for day and time entry for comet ephimerides is direct 
 entry.  You specify the starting day and time, the interval in days between 
 calculations, and the number of calculations desired.  To intelligently 
 decide whether to run for morning or evening hours, you need to know whether 
 the comet will be a morning or evening object.  The program therefore 
 displays the times of sunrise, sunset, morning and evening twilight, and the 
 rise, set, and "20 degree horizon" rise and set times of the comet.  
 Everything you need to make your decision is there when you need it. 

     Since the three time selection modes are for different purposes, their 
 ephemeris files are marked with different extensions: .EPA, .EPB, and .EPC. 
 When you want to do orbit plots, .EPA files will be listed.  For Day and Time 
 charts, only .EPB files will be listed (and you will be warned if the one you 
 choose has incompatible dates).  For any other charts, all three types of 
 files will be listed. 
>COMET EPHEMERIDES
                               Comet Ephemerides
 
     An ephemeris (plural: e-phe-mer'-i-des) is a listing of where a celestial 
 body will be when.  The ephemerides for comets produced by Deep Space 3-D 
 also tells various things relating the appearance and position of the comet.  
 Here is a summary:

   The range of dates goes down the left side of the page. 
   R.A. & Dec --Position in the sky 
   R          --Distance from sun to comet 
   Delta      --Distance from earth to comet 
   Elong.     --Elongation: angle from sun to comet as seen from earth 
   Phase      --For a comet this tells to what extent the tail points away 
                from us.  90 degrees is directly across our line of sight.
   PA         --Position angle: the angle of the tail in the sky measured 
                counterclockwise from north
   ---------
   Mag.       --Depending on the information you type in, the printout may 
                have an estimate of the magnitude (emphasis on estimate!)
 
>STAR MAP TYPES
                                 Star Map Types

     Deep Space 3-D can produce star maps in four different coordinate 
 systems, each useful for a particular purpose.

 Star Atlas Mode--Equatorial Coordinates measure positions relative to the 
 celestial poles and equator.  Right Ascension is similar to longitude, but it 
 is measured in hours (24ths of a circle) instead of degrees (360ths of a 
 circle).  This is the way star atlases display various parts of the sky.

 Day and Time Mode--Horizon Coordinates measure positions relative to the 
 horizons and the zenith.  Since the sky rotates, this changes constantly.  A 
 chart printed in this mode is good for a specific day and time.  If planets 
 are not included on it the star chart is good over a range of dates, slightly 
 earlier each night.  If you want to observe throughout the night you will 
 want a planisphere (a "Star Wheel"--see TOOLS FOR ASTRONOMY) that can be 
 taken into the field and updated from one hour to the next.  For a specific 
 celestial event, or brief observing period, however, a Day and Time mode 
 chart generated by Deep Space 3-D will give very good service.  This chart 
 mode can be zoomed to the horizon view looking in any of 16 compass 
 directions, for a larger scale, easy to read chart ideal for passing out to a 
 scout troop or group of students for an evening's sky orientation. 
-
     Ecliptic Coordinates might be termed "Solar System Mode".  This 
 projection is most useful when studying motions of objects in our solar 
 system.  The earth's orbital plane is called the "ecliptic" plane, hence the 
 name.  Any plane cutting through a sphere cuts it along a circle (imagine 
 cutting a basketball in half).  That circle where the ecliptic plane meets 
 the sky is called simply the "ecliptic".  It marks the centerline of the 
 Zodiac band, the path of the sun, moon, and planets through the sky.  To 
 print out a full sky map with the Zodiac as the center line, try an E-W 
 Mercator Projection with 360 degrees per 10 inches (for a full page) centered 
 at 0 degrees Longitude and Latitude in ecliptic coordinates.  To look at 
 comet orbits from space in such a way that the earth's orbit looks 
 horizontal, use ecliptic coordinates for the base map. 

-
     Galactic Coordinates are based on the circle of the Milky Way through the 
 sky.  Zero degrees longitude and latitude is looking directly into the center 
 of our galaxy, which happens to lie in the direction of Sagittarius.  Try 
 plotting a whole sky map (E-W Mercator Projection) down to about 5th 
 magnitude in Equatorial Coordinates.  The screen will become quite 
 cluttered,but the dense band of stars along the Milky Way will stand out 
 clearly.  (There is an upper limit of 5000 stars that can be held in the 
 allocated memory area at one time, hence the 5th magnitude limit.)  
 
     If the map is repeated, but this time in Galactic coordinates, the dense 
 star band will lie right along the center line of the page.  This is clearly 
 a useful projection when studying distributions of objects relative to the 
 plane of our galaxy.  A future update to Deep Space 3-D will have a large 
 database of galaxies, nebulae, star clusters, etc., for which this projection 
 will produce some interesting results. 
 
>MAP PROJECTIONS
                                Map Projections

     When a spherical surface is plotted on a flat map something has got to 
 give.  Stretching will always occur.  The question is what kind of distortion 
 is least bothersome for a particular application.  Some distort shapes, 
 others distort areas.  Others introduce more exotic distortions.  Generally 
 speaking, for constellation recognition preserving shapes is important.  Thus 
 the collection of projections offered here specialize in shape preserving 
 projections of one kind or another.
 
     The Stereographic Projection should not be confused with stereo viewing 
 of 3-D images.  (The possible confusion is particularly apparent in this 
 program that highlights stereo 3-D!)  Basically, to flatten out a rubber 
 ball, the edges must be stretched, causing a lengthening in the east-west 
 direction.  The Polar Equidistant Projection has just such a distortion.  The 
 Stereographic Projection compensates for the shape distortion by stretching 
 the surface radially so east-west and north-south distortions match at every 
 point.  The result is gross exaggeration of size far from the center, which 
 is the price paid for keeping the shapes correct.  Overall, the Stereographic 
 projection is a reasonable compromise for general purpose use, so it has been 
 chosen as the default projection. 
-
     The Mercator Projection was designed for making earth maps for 
 navigation.  If you follow the compass bearing of a line on a Mercator 
 Projection you will get to your destination.  It is not the most efficient 
 path, but it will get you there.  
 
     For celestial use it is more relevant to note that this map has the same 
 kind of "compensatory stretching" as the Stereographic map, so they also 
 preserve shapes at the expense of gross area distortion far from the center 
 line.  But whereas the Stereographic projection is accurate at a point, the 
 Mercator projection is accurate along a line.  It is a good choice if the 
 subject of interest is primarily oriented along one particular direction, 
 such as a Zodiac band or any other wrap-around view of the sky.  Two 
 variations are offered here: N-S and E-W, depending on the nature of the 
 material to be mapped. 

     The Gnomonic Projection is the kind of a projection produced by a camera.  
 You might think this would be the ideal projection, but both size and shape 
 are grossly distorted far from the center.  It is, however, a useful 
 projection for small areas, especially if computer generated star maps are to 
 be overlaid onto or otherwise correlated with photographs. 
>STELLAR MAGNITUDE
                               Stellar Magnitude

     Star brightness is measured on a "magnitude" scale.  This is a scale 
 originally based on naked eye estimates of brightness.  First magnitude 
 represents the brightest category or "First Rank" stars.  Sixth magnitude 
 represented the faintest stars visible to the unaided eye.  Thus increasing 
 magnitude implies decreasing brightness.  Telescopes have extended the scale 
 to much higher numbers and photometers have increased the precision to 
 several decimal digits.
 
     Generally speaking, if you want to plot naked eye stars, you should cut 
 off somewhere around 6 or 6.5, depending on whose eyes we are talking about: 
 about 6000 stars.  If you want a whole sky map, that is far too many stars 
 for a useful chart.  The starter database goes down to a little beyond Mag. 
 7.2.  That is around 19,000 stars.  The whole 77 file database go down to 
 about 10, with spotty coveage near the limits.
 
     The larger database is most useful when you want to generate a detailed 
 view of a small part of the sky.  With the full database you could plot the 
 Pleiades star cluster, for instance, to a scale of 1/2 degree per inch, and 
 still have a field rich in stars. 
>USING THE CURSOR
                                Using the Cursor

     Once a map is plotted there are a number of interactive features accessed 
 with the function keys.  
 
 <F1> brings up a cursor.  Move it with the arrow keys, for small jumps, or 
 with the arrow keys in conjunction with the Shift key for single pixel fine 
 adjustments.  If the cursor is centered on any object (star, planet, comet, 
 etc.) the object will be identified.  If two stars are overlaid on the same 
 pixel, both stars will be identified in sequence.

 <F7> uses the cursor in a different way.  If planets or comets are "overlaid" 
 onto the star map, the F7 cursor will jump from one to the next.  For comets 
 and planets generated by the What's Up routine it will simply give the name 
 of the object.  For comets generated by the ephemeris routine, it will give 
 the name of the comet, and also the date, since the different images are for 
 different dates.  One particularly impressive use of the F7 cursor is to 
 trace out the path of a comet orbiting the sun along with the earth.  See the 
 COMET PATHS FROM SPACE section for more details. 
 

>SAVING AND RESTORING MAPS
                           Saving and Restoring Maps

     Star maps may be saved with the F2 function key.  Simply give the name 
 to be used for the map file.  A saved map can be restored much faster than it 
 can be computed in the first place because all the heavy math has already 
 been done.  This feature will be especially appreciated by those of you who 
 have the older slower PC and XT type computers without math co-processors.  
 
     To restore a map, choosed the DISPLAY SAVED MAP option at the Main Menu.  
 A directory of all saved maps will be generated from which you can select a 
 map with the scroll bar.  Once a map is restored it is ready for any function 
 that could be performed on a freshly computed map.

>ZOOMING
                                    Zooming

     To Zoom a star map that was printed in Equatorial, Ecliptic, or Galactic 
 Coordinates, type the F3 function key.  A rectangular box will appear to the 
 same proportions as the full-screen map.  Manipulate the box with the PgUp 
 PgDn and Arrow keys to frame the view that is desired.  For finer adjustments 
 use the same keys in conjunction with the Shift key.  Once the map has been 
 zoomed, typing F3 again will restore the original dimensions.  If the print 
 option is chosen while a map is zoomed, the zoomed view will be what is 
 printed out. 
     The Zoom feature is different for the Horizon Coordinates (Day and Time) 
 map.  Here the Zoom takes you from a whole sky view to a horizon view.  
 Directions are specified by the points of the compass: N, S, E, and W specify 
 the quadrants; NW, NE, SW, and SE split half way between the primary 
 divisions; N-NE, E-NE, E-SE, S-SE, etc. split the difference once again for a 
 total of 16 possible directions.  The Left and Right Arrow keys step by 
 16ths, the up and down arrow keys step to the nearest 8th, the PgUp and PgDn 
 keys step to the nearest quadrants, and the Home and End keys jump to North 
 and South.  ESC takes you back to the whole sky view.
>CONSTELLATIONS
                          Constellation Lines & Names

     Constellation lines are drawn with the F4 key.  Once they are drawn the 
 constellation names automatically pop up.  The constellation names present a 
 bit of a problem if the goal is to use them on printouts.  First, they tend 
 to obscure the stars, and secondly, the screen representations (which differ 
 from one type of video monitor to another) may bear little resemblence to the 
 actual text size on paper.  Furthermore, not all constellation names that 
 show up on the screen may be desirable.  Sometimes only a tiny corner of a 
 constellation intrudes on the edge of the paper and you may want to ignore 
 it.  Or, if you are dealing with students, you may want to focus their 
 attention on a few constellations only. 

     To solve these problems as conveniently as possible the following method
 has been devised:
 1. The constellations on screen are in the smallest font for that screen 
    provided by the language in use (Turbo Pascal).
 2. They are popped into position automatically for quick and easy 
    identification of constellations even though they might overwrite 
    significant details of the maps.  Each constellation name is associated 
    with the brightest star of a constellation that is shown on the screen, 
-   usually displayed a short distance to the right of the star. 
 3. By typing F4 a second time you can enter a mode where you will cycle 
    through the constellation names, forward through the alphabet with the 
    ENTER key, or backward with the Backspace key.  The highlighted name can 
    be positioned with the arrow keys, in conjunction with the Shift key for 
    finer spacing. 
 4. As the name is being moved, it is represented by a small rectangle that 
    represents the computed size of the printed version of the name.  This 
    will aid you in placing it properly.  Once the ENTER key is typed the name 
    will pop to the location of the rectangle. 5. Names may be deleted with 
    the DEL key when they are selected in the cycle. 6. If you plan to print 
    out a zoomed view, you should postpone positioning the names until your 
    final step before printing.  Names positioned for one view do not 
    necessarily match what would be desirable in a zoomed view, so the offsets 
    are canceled upon zooming.  Deleted names are also resurected in this way.

>PLANETS, ETC.
                                 Planets, Etc.

     Planets come in two varieties: those that outshine most if not all of the 
 stars (Mercury, Venus, Mars, Jupiter, and Saturn), and those that require 
 optical aid even to be seen (Uranus [borderline], Neptune, and Pluto).  The 
 positions of the Sun, Moon, and all the planets are computed in the What's Up 
 routine.  This information may be displayed on a star map (any variety) by 
 pressing the F5 key.  On first press the sun, moon, and bright planets will 
 be shown.  To get Uranus, Neptune, and Pluto, press it a second time.  Any 
 comets computed with the What's Up routine will also be shown at the same 
 time.

     The planets are identifiable by their symbols.  Further identification is 
 possible using the F7 key to jump from one to the next, displaying their 
 names in a box at the top left corner of the screen.  They may also be 
 identified manually by placing the F1 cursor on the symbol.  For symbols with 
 a symmetric portion, such as Mercury, Venus, Mars, and Uranus, the pixel to 
 hit is the center of the symmetric portion.  The asymmetric symbols have a 
 small dot added for targeting.

>COMET PATHS FROM EARTH
                             Comet Paths from Earth

     Comet paths seen from earth could be termed "finder charts".  They can be 
 plotted on any kind of base map, but equatorial "Star Atlas" mode and "Day 
 and Time" mode charts would usually be the most useful.  For detailed views 
 plot them at intervals of 1-5 days for no more than 10 or 15 calculations at 
 a time.  Find the center of the path from the ephemeris as a best first guess 
 for the map coordinates to use.

     A word here about the displayed "tail" is in order.  The tail displayed 
 by the program is in no way a prediction of actual tail length: it is fixed 
 at an artificial a 1/10 AU length (about 10 million miles).  However, it does 
 reflect the effect of distance and phase on apparent tail length, and it is 
 shown at the correct position angle on the sky.  This can be a great 
 observing aid if you think you detect a possible faint tail and wonder if it 
 is in a plausible direction (some comets have anti-tails, remember).  The 
 length of the tail shown is the length the tail would appear if it were 
 actually 1/10 AU long.  If the observed tail is half that long you know, 
 then, that the physical length is 5 million miles long.  The plotted tail is 
 thus not a prediction, but it is a yardstick. 
- 
     Another interesting question arises when plotting a comet path on a Day 
 and Time mode star map.  By definition a Day and Time mode map is for a 
 particular day and time, yet also by definition, a comet path is extended 
 over a period of time.  How can the two be meaningfully combined?  The method 
 of display here is somewhat of an innovation, but I think it is a very 
 helpful way to treat the data.  
 
     On the Day and Time mode maps, two paths are shown: one follows the path 
 of the comet relative to the stars, the other follows the path of the comet 
 relative to the horizons.  If the starting day for the ephemeris matches the 
 date of the map, the two initial marks will coincide.  But then, since the 
 sky rotates over the plotted interval, the two paths diverge from there.  The 
 normal plot (plus mark with a tail) indicates the path relative to the stars.  
 The other path is marked with X's.  This is the path that for a given time of 
 night shows when the comet will be highest above the horizon and how long it 
 will remain in the observable portion of the sky.  Some comets are "horizon 
 huggers", so this information is critical to evaluating their potential 
 visibility.
>COMET PATHS FROM SPACE
                             Comet Paths from Space

     When a comet ephemeris is generated with the "A" option (symmetric about 
 perihelion) it is suitable for tracing out the whole orbit, or a significant 
 portion of its inner orbit, as seen from a point off the earth.  To create a 
 sample orbit view follow this recipe: 
 
 1. Pick a comet and generate an ephemeris using day and time option A.  Take 
 all of the default settings from there on out.  When asked for a file name, 
 choose the default name (good for "scratchpad" storage) or choose a different 
 file name. 
 
 2. Generate an Ecliptic Coordinate star map (Option C).  Select by 
 Coordinates (option B): any Longitude you want (0 is ok), but some negative 
 angle (-25 would be good) for the Latitude.  That is so you will be looking 
 down on the solar system at an angle from above.  The direction specified is 
 the direction we are looking TOWARD.  Take all the defaults for scale, 
 projection, etc. (or choose the Gnomonic projection for somewhat better 
 renditions of ellipses and parabolas). 
-
 3. When the star map comes up choose Option 6 for comet paths, and select to 
 see it from Space rather than earth.  Take the default viewer distance (5 AUs 
 is about the distance of Jupiter) and at the menu select the ephemeris you 
 have just generated.

 4. The sun will be plotted first, followed by a comet path.  When the comet 
 gets within 6 months of perihelion the earth will also kick in, so both will 
 be orbiting the sun together.

 5. Now comes the good part.  Choose the F7 cursor option.  The cursor should 
 land on the sun and a box at the top left corner of the screen will say SUN.  
 Typing the ENTER key, the cursor will jump sequentially to each position that 
 was plotted, identifying the object and the date.  To speed up the process 
 type the END key to disable the identification box.  (There is no mention 
 of the END run option in the program itself; you have to learn it here.)  
 Typing it again will bring the box back, but leave it off for now.  Hold down 
 the ENTER key for an animated view of the earth-comet encounter.  The motion 
 can be stopped and the END key typed to bring up a date at any point.

 6. Several comets can be put on the screen simultaneously as long as the 
 total number of points (counting heads, tails, sun and earth) does not exceed 
 500.  If tails are left off, more comets can be included.
>CLEARING
                               Clearing Overlays

     The Planet and comet images on the video screen can be though of as 
 overlays superimposed on a star base map.  Typing F8 (twice for safety) 
 clears the overlays without having to start the map computation from scratch 
 You can thus experiment with various options without committing to them for 
 the final printing.
>3-D / LARGE AND SMALL
                             3-D / Large and Small

     Space is 3-dimensional.  The sky we see is a two dimensional surface 
 because of the limitations of our depth perception.  At great distances all 
 things look the same distance away, hence we seem to be at the center of a 
 sphere.  In other words, the sky is an illusion.  It takes the illusion of 
 stereo graphics to dispell the illusion of the sky.
 
     To see 3-D you need two points of view that are sufficiently far apart 
 compared to the distances of the objects being viewed.  In a room, normal eye 
 spacing gives ample depth perception.  Depth is easily judged 10 or 20 feet 
 away by eyes that are about 2.5 inches apart: a factor of 50-100 eye 
 spacings.  Keep this in mind when it comes to plotting stereo views of the 
 stars.  A simulated "eye spacing" of a few tenths of a light year will bring 
 out depth well into the distance among the stars.  Over doing the eye 
 separation is like trying to look at something an inch or two in front of 
 your face.  On the other hand, be flexible and experiment.  See for yourself 
 the difference changing the eye spacing makes and find your own favorite 
 range.
-
     To see 3-D you probably need a viewer.  Some people can teach themselves 
 to view the small scale 3-D views without a viewer, one eye looking at each 
 frame, but the viewer makes the process much easier.  The small scale 3-D 
 views are limited by the actual spacing of human eyes: the squares can be no 
 larger than the distance between the eyes.  The small scale viewer that comes 
 with the registered program helps focus each eye onto a separate picture.  
 The brain fuses the information from the two slightly different flat pictures 
 into a single 3-dimensional image.

     The large scale 3-D printouts are for use with a table-top viewer using 
 mirrors.  With the large viewer two 8-1/2 x 11 sheets can be viewed side-by-
 side for an incredible sensation of depth.  It's like sticking your head into 
 the universe.
 
 Some of the things to notice when viewing the stars in 3-D:

 --Some stars are bright because they are close, whereas others are bright 
   because they are BRIGHT.
 --Some pairs of stars are close together in the sky but far apart in space.  
   Other stars are far apart in the sky but close to each other (and us) in 
   space. 
 --Some familiar constellations contain actual star groupings, others only 
-  apparent groupings.
\
     Besides viewing the stars in 3-D, try viewing the planets and comets in 
 3-D.  When solar system objects are present the stars are flat in the 
 background since they are so much farther away by comparison.  Eye spacings 
 are now specified in Astronomical Units (AUs) rather than light years.  1 AU 
 is the distance from the earth to the sun.  An AU is to a light year as an 
 inch is to a mile (almost exactly!).  Planets are really very local.  Using 
 the distance to eye spacing ratio of 50 or 100 as discussed above, a 3-D view 
 looking at the sun and inner planets from the earth should require an eye 
 separation of only about 0.01 to 0.02 AUs.  0.1 AU is adequate for viewing a 
 comet orbit from the distance of Jupiter.

     When comets are seen in 3-D the main point of interest is the orientation 
 of the orbits relative to the earth's orbital plane.  Most of the solar 
 system is flat, but comets come in from all angles.  The inclinations stand 
 out dramatically in this format.
-
     The mechanics of getting the 3-D views is simple.  For small scale 3-D 
 hit F9.  A square frame will appear on the screen.  Zoom it in and out with 
 the PgUp and PgDn keys and move it around with the Arrow keys.  Make fine 
 adjustments with the same keys in conjunction with the Shift key.  Hit ENTER 
 when the desired view has been selected.  Whatever has been chosen will be 
 scaled to a 2.5 inch format and printed in stereo.

     The large scale 3-D views are whole page printouts and are requested 
 through the F10 printout option.  Simply type F10 as printing normally, but 
 answer yes to whether you want the printouts to be in 3-D.
\
>PRINTOUTS
                                   Printouts

     To make printouts of a whole map or a zoomed view, display whatever 
 features are desired on the video screen and then print by typing the F10 
 key.  You will be asked whether you want the view in 3-D or flat.  This would 
 be for the large scale 3-D view printed out on two consecutive pages.  If 
 you have chosen a horizontal format and have the large viewer the two pages 
 can be left attatched for viewing in stereo.  Keep in mind that each picture 
 in a stereo pair has points that are offset from their normal positions, so 
 the 3-D option is inappropriate if you intend to use the printouts as finder 
 charts at night.  

>

