Use this window to select a location anywhere on earth, either by selecting a location in the location list box, or by directly entering the longitude and latitude of the desired location.
The locations shown in the location list box are the locations listed in the location database file, nvlocations.txt, which is kept internally within the program unless the user chooses to write it externally. (This allows the user to edit the locations to their preferences - see directions at the top of nvlocations.txt). Most of the locations have been configured to know when daylight saving time (DST) is in effect. When this is known, the "Auto DST" checkbox will be enabled and checked (by default). Most users will not need to change this setting. To override, uncheck the "Auto DST" checkbox and then check or uncheck the "DST on" checkbox to manually set whether DST is in effect. For locations that have not been configured to automatically know when DST is to occur (in the nvlocations.txt file), the "Auto DST" checkbox will be disabled, and the user must manually set DST. Once a location and DST have been set, press "OK Location" to go to the new location.
Alternately the new location can be specified by directly entering its longitude and latitude. Longitude is entered as sddd:mm where s is the sign (+, -, or blank), ddd are degrees ranging from 0 to 180, and mm are minutes ranging from 0 to 59. Longitude is negative for locations west of 0°. Latitude is entered as sdd:mm where s is the sign (+, -, or blank), dd are degrees ranging from 0 to 90, and mm are minutes ranging from 0 to 59. Latitude is negative for locations south of the equator. Time zone is entered as shh:mm where s is the sign (+, -, or blank), hh are hours ranging from 0 to 12, and mm are minutes ranging from 0 to 59. Time zone is negative for zones west of Greenwich, England, and represents the time difference between the location and Greenwich. Check or uncheck the "DST on" checkbox to manually set whether DST is in effect. Once coordinates and DST have been set, press "OK Coordinates" to go to the new location.
Note: Changing the location will change the time indicated in the information bar above the main star window if the new time zone differs from current time zone. This allows the user to hop from location to location while maintaining the same time in the first location. For example, hopping from Denver to Dallas changes the time from say 1:00 to 2:00, because the time in Dallas is 2:00 when the time in Denver is 1:00.
When DST is not automatic, DST can also be manually set via the "Set local date/time" window.
Press "OK Location" to accept a location from the list box.
Press "OK Coordinates" to accept a location based on the specified
longitude/latitude coordinates and time zone.
Pressing "Cancel" rejects any changes.
If desired, use the "Save location" selection from the "File" pull down menu to save the current location so that Night Vision begins there when starting. "Save location" also saves the current DST setting.
Note: When "Auto DST" is enabled and checked, transition dates to and
from DST are determined by information within your computer's Java
installation. Unfortunately this information contains no historical data.
Thus the same transition rules are applied to all years. For example,
in 2007 the USA changed the rules for the dates when DST starts and ends,
expanding the amount of the year when DST is in effect. To be accurate,
your Java installation should be updated with the latest DST rules.
However these same rules are also applied to prior years when DST was
determined differently. Thus for prior years "Auto DST" should be
unset so that DST can be set manually, depending on date.