Shadows is a software package for the calculation and drawing of sundials and astrolabes, available as a freeware in its base level.
It has been developed by François Blateyron, software developer and amateur astronomer, who made it available on Internet since 1997 and continues to improve it.[1] It is used worldwide by thousands of sundial enthusiasts.[2] It is compatible with Windows 11/10, 8.x and 7. Shadows is available in three levels: Shadows is a freeware; Since version 3.0, it also supports the creation of astrolabes.
Shadows is software restricted to the Windows operating system. It is simple to use but does not aim to be universal. It
draws the sundial on screen and prints it to various scales to act as a template during fabrication. The sundials show solar time and can include longitude correction and equation of time. It also can draw ancient or unequal hours such as Italian and Babylonian and even draw azimuth and altitude curves. It has an animation feature so the shadow of the style can be simulated on the screen. The results can be copied as an image or a vector graphics (metafile or DXF) for use in CAD programs or machine tools.
In 2005, the French astronomical society, Société Astronomique de France (SAF) awarded Blateyron with the Julien Saget prize for the Shadows software.[3]
The Astrolabes are interactive and can be manipulated on screen by rotating the Rete and the Alidade using the mouse.
Several curves and graphs are available: equation of time, solar graph with horizon mask, duration of the day, direction rose.
It is now available in French, English, German, Spanish, Italian, Portuguese, Brazilian Portuguese, Dutch, Hungarian, Slovenian, Greek, Polish and Russian- the translation were provided by the users.[citation needed]
Features of the three levels of Shadows
Shadows is supplied in three versions.
Vertical sundial drawn by Shadows.
Shadows: Freeware version
Plane sundials with polar style (horizontal, vertical declining, equatorial, polar, meridian dial)
Drawing of the sundial to scale 1; Any dimension, orientation or reclination
Suitable for any location on Earth, on northern or southern hemisphere (2800 locations pre-installed)
Drawing of the style to scale 1, ready to be cut out
Tables of coordinates of hour lines and declination lines
Drawing of declination arcs and hour lines (solar or mean time), with or without longitude correction
Moveable, resizable text frames, with list of pre-installed mottoes
Drawing of the curve of equation of time, in various shapes
Drawing of compass and azimuth circle
Full on-line help, user interface translated into 17 languages.
