The Location settings tab contains the options related to your site coordinates and possibilities to synchronize them. It is important to define the coordinates because they are used by Darkness Clock, Deep Sky Darkness Calculator, the filter of visible objects in Objects Browser and checking if object is above horizon on GoTo.
Defines an offset from the calculated Astro Twilight. This allow to define that astro night starts X minutes earlier and ends X minutes later. By this way the automated imaging cans start earlier and end later. This offset is used by the #ConditionalStop script command, by SessionCraft and by manually scheduled plans via Start options.
Defines the Air Mass Limits for calculation of Maximum Imaging Time and Imaging Time Left in Object Browser. The Air Mass value defines how much atmosphere there is between the us and the object. In Zenith the thickness is the smallest possible - one atmosphere (Air Mass 1.0). On horizon the thickness is equal to 35 atmospheres. It is considered that imaging through 2 atmospheres (Air Mass 2.0) or less gives best imaging results. This corresponds to altitude above horizon of 30 degrees or more.
When the desired altitude limit is entered the corresponding air mass value will be displayed.
When enabled the Nautical Twilight will be used instead of Astro Twilight as definition of the astro night. This is useful in the areas with high north/south latitude, with long nautical twilight and possibility to do narrowband imaging. This affects the #ConditionalStop script command, SessionCraft and the manually scheduled plans via Start options.
The current site coordinates will be used to set the coordinates of the telescope as soon as it is connected.
Note: If you want to export location information to EQMOD/EQASCOM you have to enable the option "Allow Site writes". To open the EQMOD settings panel use either:
The APT Settings dialog box is accessible from 
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