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-
- ------------------------------
- STARVIEW by Neil Parry (C)1993
- ------------------------------
-
- IMPORTANT!
- ----------
-
- You are free to distribute this program providing that all the files remain
- unchanged and accompany the program. StarView is a shareware program,
- so if you find it useful, please send £5 to the following address:
-
- Neil Parry.
- 35 Preston Lane,
- Bilton,
- Hull.
- HU11 4DE.
-
-
- 1. Introduction
- ---------------
-
- StarView is a mouse-operated program designed to show graphically the
- positions of the stars and planets from any point on the earth. Most stars
- above magnitude 4.5 are shown (over 850 in total), more than 100 with their
- proper names. The outlines and names of all 88 constellations are also
- given. Other features include zooming in/out, finding a constellation,
- adjusting the level of detail shown, saved preferences and the ability to
- print a view of the sky. The program was written using HiSoft's Power BASIC.
-
-
- 2. Using the program
- --------------------
-
- 2.1. Entering the time and place.
-
- The 'Change Time and Place' window can be accessed by clicking on the
- time/place information boxes at the top of the screen. It will also be
- brought up automatically when the program is first run. Click in the text
- boxes to type in the details as follows:
-
- Date - in the format DD.MM.YYYY, any date from 1950 to 2050 is valid.
-
- Time - local time in the format HH.MM (24-clock).
-
- (If you have an internal clock, click on the NOW box and the current
- date and time will be entered automatically.)
-
- Zone Offset - The offset between your local time and Greenwich Mean
- Time, in hours. For instance, this would be 0 in Britain
- in winter, -1 for British Summer Time, +10 for Western
- Australia, etc.
-
- Latitude - of your location in degrees 0-90 followed by N or S.
-
- Longitude - of your location in degrees 0-180 followed by E or W.
-
- Both latitude and longitude can be entered with up to 2 decimal places.
-
- When finished click on EXIT, the program will calculate the star positions
- for the time and place you've entered. If any of the values were invalid the
- screen will flash and the cursor will be positioned on the value in error to
- allow you to correct it.
- If you've changed your mind click on CANCEL to return to the program.
- The SAVE button will save your current time & place to disk (make sure the
- disk isn't write-protected). These values will then be loaded up whenever
- the program is first run.
-
-
- 2.2. Horizon View and Zenith View.
-
- StarView displays the night sky in two separate views. The horizon view
- shows a portion of the sky from the horizon up to an altitude of 70 degrees.
- The zenith view shows a circular view of the sky centred around the zenith
- (the point in the sky directly above your head), you can view the whole sky
- at once in this mode. To switch between these two views, click on the icon
- at the bottom right of the screen (a circle or a square depending on which
- mode you're currently in).
-
-
- 2.3. Scrolling and Zooming the sky view.
-
- Horizon View:
- On the horizon view are scales to show the azimuth (the direction you're
- facing) and the altitude (the angle up from the horizon). These scales also
- act as scroll bars for the view. Click in one of the bars and drag up/down
- or left/right to scroll the view. Note that the altitude bar won't scroll
- when on maximum zoom-out as it is at the limit of 0-70 degrees.
- To zoom in or out, click on the zoom bar at the bottom left of the screen
- and drag left/right.
-
- Zenith View:
- The zenith view shows the points of the compass around the edge of the
- circular view, to rotate this view click on one of the compass points (or
- anywhere just outside the circle) and drag the pointer around to adjust the
- view to the angle you want.
- Zooming is achieved using the zoom bar, as with the horizon view. The zoom
- is always centred around the zenith, the number next to the zoom bar being
- the radius of sky currently being shown.
-
- In addition, (in either view mode) the NSEW buttons on the left of the
- screen can be used to centre the view on a particular compass direction.
-
-
- 2.4. The SetUp Menu.
-
- Clicking on the SETUP button will bring up a menu of options which allow you
- to adjust the level of detail shown on the sky view. The options are as
- follows:
-
- Constellations Identified (MAIN/MOST/ALL):
- Selects the number of constellations outlined and labelled on the screen,
- MAIN shows just the brightest or most obvious constellations, MOST shows all
- except the faintest and ALL displays all of them.
-
- Constellation Outlines (OFF/ON):
- Selects whether constellation outlines will be drawn or not.
-
- Constellation Names (OFF/ABBR/FULL):
- Selects how the constellation names will be displayed. FULL shows the full
- constellation name, ABBR shows a three letter abbreviation.
-
- Star Names (OFF/SOME/ALL):
- Over 100 star names are stored by the program, ALL will display all of them,
- SOME will just label the brightest.
-
- Planets (ON/OFF):
- Selects whether the planets will be shown or not. Note that the brightness
- of the planets is not given, just the position, and in fact the outer three
- planets (Uranus,Neptune & Pluto) are not actually visible with the naked
- eye.
-
- Star Symbols (DOT/BIG):
- Selects how the stars are displayed on the sky view. DOT represents a star
- as a single dot that can be a different brightness depending on the
- magnitude of the star. BIG represents brighter stars as a larger dot, which
- is useful when printing out the screen.
-
-
- 2.5. Finding a constellation.
-
- Clicking on the FIND button will bring up a list of all 88 constellations.
- Click on a constellation and if it is visible, the program will find it and
- return to the horizon or zenith view depending on where in the sky the
- constellation currently is. If the constellation isn't visible, NOT VISIBLE
- will flash at the bottom of the screen.
- This option also displays the abbreviations and meanings of the
- constellation names.
-
-
- 2.6. Printing the screen.
-
- Clicking on the PRINT button will print the screen. Note that this is simply
- a graphic screen-dump and will be printed according to the printer settings
- in Preferences. I've found that printing a black-and-white, negative image
- with a threshold value of 14 produces good results. It also helps having the
- star symbols set to BIG (in the Setup Menu) in order to determine the
- magnitudes of the stars on a black-and-white print.
-
-
- 2.7. Quitting the program.
-
- Click on QUIT to return to the Workbench.
-
-