Shadows is a software package for the calculation and drawing of

sundial A sundial is a horological device that tells the time of day (referred to as civil time in modern usage) when direct sunlight shines by the apparent position of the Sun in the sky. In the narrowest sense of the word, it consists of a flat ...

s and

astrolabe An astrolabe ( grc, ἀστρολάβος ; ar, ٱلأَسْطُرلاب ; persian, ستاره‌یاب ) is an ancient astronomical instrument that was a handheld model of the universe. Its various functions also make it an elaborate inclin ...

s, 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. It is used worldwide by thousands of sundial enthusiasts. 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.

Description

Shadows calculates various types of

s: * plane sundials with polar style (any orientation or reclination) * horizontal or vertical

analemmatic sundial Analemmatic sundials are a type of horizontal sundial that has a vertical gnomon and hour markers positioned in an elliptical pattern. The gnomon is not fixed and must change position daily to accurately indicate time of day. Hence there are no h ...

* horizontal or vertical bifilar sundial * cylindrical sundial as well as

s: * planispheric astrolabe * universal astrolabe * mariners astrolabe ''Shadows'' is software restricted to the

Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for serv ...

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 In mathematics, an equation is a formula that expresses the equality of two expressions, by connecting them with the equals sign . The word ''equation'' and its cognates in other languages may have subtly different meanings; for example, in ...

. 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 AutoCAD DXF (Drawing Interchange Format, or Drawing Exchange Format) is a CAD data file format developed by Autodesk for enabling data interoperability between AutoCAD and other programs. DXF was introduced in December 1982 as part of AutoCA ...

) for use in CAD programs or machine tools. In 2005, the French astronomical society,

Société Astronomique de France The Société astronomique de France (SAF; ), the French astronomical society, is a non-profit association in the public interest organized under French law (Association loi de 1901). Founded by astronomer Camille Flammarion in 1887, its purpose ...

(SAF) awarded Blateyron with the ''Julien Saget'' prize for the Shadows software.Prix Julien Saget SAF 2005
/ref> The

Astrolabe An astrolabe ( grc, ἀστρολάβος ; ar, ٱلأَسْطُرلاب ; persian, ستاره‌یاب ) is an ancient astronomical instrument that was a handheld model of the universe. Its various functions also make it an elaborate inclin ...

s are interactive and can be manipulated on screen by rotating the Rete and the

Alidade An alidade () (archaic forms include alhidade, alhidad, alidad) or a turning board is a device that allows one to sight a distant object and use the line of sight to perform a task. This task can be, for example, to triangulate a scale map on site ...

using the mouse. Several curves and graphs are available:

, 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.

Features of the three levels of Shadows

Shadows is supplied in three versions. 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. Shadows Expert: Intermediate version, shareware (in addition to standard ''Shadows'' features) * declining-reclining plane sundials *

Analemmatic sundial Analemmatic sundials are a type of horizontal sundial that has a vertical gnomon and hour markers positioned in an elliptical pattern. The gnomon is not fixed and must change position daily to accurately indicate time of day. Hence there are no h ...

s * Cylindrical sundials (shepherd's dial, armillary sphere, ...) * Tables of solar and astronomical ephemeris * Drawing of Italian and Babylonian hours * Insertion of images for decoration * Export of data and images * Drawing of the construction layout (epure) * Simulation of the shadow cast by a roof * Animation in orientation and reclination of the sundial * Tool for the calculation of the wall orientation * Direction rose * Mariners astrolabe Shadows Pro: Full version, shareware (in addition to ''Shadows Expert'' features) * planispheric and universal

s * vertical declining

* Bifilar sundials * Drawings in azimuth and altitude * Sidereal hours, unequal hours * Animated 3D view of sundials * 3D view of multiple sundials * Solar graph with horizon mask * Export of drawings in WMF and DXF (

AutoCAD AutoCAD is a commercial computer-aided design (CAD) and drafting software application. Developed and marketed by Autodesk, AutoCAD was first released in December 1982 as a desktop app running on microcomputers with internal graphics controllers. ...

) * Export of animations in AVI * Tool for the calculation of sundial parameters from a photograph * Efficiency graph of a

solar panel A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...

History of versions

* version 5.0 (March 2022) * version 4.5 (June 2020) * version 4.4 (August 2019) * version 4.3 (May 2019) * version 4.2 (October 2018) * version 4.1 (November 2016) * version 4.0 (June 2014) * version 3.5 (August 2012) * version 3.4 (November 2011) * version 3.3 (December 2010) * version 3.2 (January 2010) * version 3.1 (July 2009) * version 3.0 (May 2008) * version 2.2 (January 2006) * version 2.1 (January 2005) * version 2.0 (March 2004) * version 1.6 (January 2001) * version 1.5 (February 1999) * version 1.0 (September 1997)

References

External links

Official Web site of Shadows

The Astrolabe
by James E. Morrison {{Portal bar, Software, Astronomy, Stars, Mathematics, Education, Science Astronomy software

Description

Features of the three levels of Shadows

History of versions

See also

References

External links