How to create and use sundials and astrolabes?

Shadows Pro is a software package for designing sundials and astrolabes, developped by François Blateyron. It allows you to easily create a sundial customized for your location and then to build it thanks to printouts to scale. Shadows is free in its base level. Shadows is used by thousands of users around the world. Discover the world of sundials on this web site through educational pages and photo galleries.

Shadows software

The Shadows software is acclaimed around the world for its ease of use and its power. Create your first sundial customized for your place. It does not require technical skills.

Discover Shadows »

Discover Shadows


Learn how to read time on a sundial; Discover the different types of sundials and browse through the gallery of sundial photographs from France and all around the world.

Discover sundials »

Discover sundials


An astrolabe is a great astronomical calculator and at the same time a magnificient piece of craft art, usually seen in museums. Learn how it works and use a virtual astrolabe on screen.

Discover astrolabes »

Discover astrolabes

Shadows software

Shadows is a software package for calculating and drawing sundials and astrolabes. Its base version is free. With Shadows, create and print your first sundial in a couple of minutes.
Shadows Pro brings powerful advanced and professional features. It requires a paid license.

Free! Download Shadows »   Buy a Shadows Pro license »  

Features »   Read the on-line user manual »  

Shadows software home page


"I must commend you for developing such a magnificent tool for the dialist and dial-minded among us. Shadows is surely a major contribution to the field, and I am looking forward to exploring the software's capabilities. Thank you for your dedication in bringing such a magnificent idea to fruition."

"Dear Francois, Thanks for producing such a fantastic and easy to use program. I have already told one of my friends about it and we intend to make a couple of sundials for our back yards. I have access to a CNC milling machine so I can't wait to produce the hour plate. I'll send you a picture when they are done. So much information on your web site that really interests me. Great job!"


Discover sundials with a series of educational pages. Learn how to read time on a sundial and to use the equation of time to correct solar time. Browse through photographs of sundials of France and other places.

Learn how to read time on a sundial »   Photographs of sundials »  


An astrolabe is an astronomical calculator in the shape of a disk in brass with mobile elements and engraved scales. Its drawings are based on the stereographic projection. Put your hands on various types of astrolabes and discover how to use them.

Learn how astrolabes work »   The planispheric astrolabe »  

Subscribe to our mailing list

* indicates required

Sundial - Cadran solaire - Sonnenuhr - Reloj de sol - Cuadrante solar - Meridiana - Orologio solare - Relógio de sol - Quadrante solar - Zonnewijzer - Zegar słoneczny - Sluneční hodiny - солнечные часы - слънчев часовник