Shadows

While sundials are rather well-known devices used to approximate the time using the Sun's shadow, astrolabes are more advanced inventions that can also be used for predicting the position of various stars, or to triangulate a location.

Shadows is an application that enables you to design your own sundials and astrolabes by making use of the provided templates and premade calculations for various places around the world. You can choose between horizontal, polar or equatorial sundials, as well as one of the many countries and location parameters included within the utility. The application also delivers the coordinates and the time zone parameters for each location and you can even edit them or add your own.

After you make your choice, the sundial's esthetics can be modified to include a 24-hour format numbering system, additional lines for every 30, 15 or 5 minutes and a custom shape, ranging from rectangular, to elliptical and hexagonal. You can also choose whether to draw an analemma curve at each hour line and shift it by the longitude correction.

In order to find out the mean time for a given date, you must consult with the equation of time, which is a curve you can read in order to add the correct value to the solar time and obtain the mean time. Shadows displays a graph depicting the time in minutes you should consult, which can then be added to your value.

After you are done designing your sundial or astrolabe and you have set up all the parameters you need, the drawing can be easily printed directly from the application, together with all of the lines and markings you have chosen to include on it. You can also export the file as an AutoCAD-compatible DXF document.

Despite it being an utility designed mostly for those of you who are experienced with sundials and astrolabes, the actual process is straightforward and intuitive, as long as you are familiar with the terms or you do a bit of research beforehand.