So what is true solar time in comparison to the time you read on your watch dial? Well find out in this video with a very special professor that will demonstrate how a sundial actually works.

The idea of this sundial came from the Espace Horloger of the Vallée de Joux and was co-developed with the help of legendary traditional watchmaker Philippe Dufour, but also the very interesting carpentry Bodenmann workshop, as well as Astroval, the astronomical association of the Vallée, and the Engineering School of the same Vallée.

And if you're interested with any of the sundials proposed in this video, you can purchase them in the boutique section of this website and please remember that it's for a good watchmaking cause as it supports the Espace Horlogers of the Vallée de Joux.

This video report was shot in La Vallée de Joux: