This dial was portion of my submission to the 1992 DesignCAD design contest. The complete entry won third prize.
Some of the indications are difficult to pick out at this scale. Each set of lines and curves is delineated in separate drawings below.
The dial indicates:
- Solar time on the green hour lines.
- Standard time on the analemmas (figure eights) surrounding the hour lines.
- The sun's declination (also its position in the Zodiac) along the orange curves.
- The sun's altitude on the curved yellow dotted lines.
- The sun's azimuth on the vertical yellow dotted lines.
- The Babylonian and Italian hours by the oblique blue and white lines.
I left two little clues in the full drawing to show that my original program was reflecting the facts of solar life.
- Note the confluence of lines at the upper left. The little green
line is the 6am hour line, which falls just off the dial. The horizontal white line is the time of sunrise. On the equinox, the sun rises at 6am. Note that the 6am line, the sunrise line, and the orange equinox line meet at a point.
- The extra dotted yellow altitude curve below the dial represents the maximum altitude the sun can reach at the dial's location. Note that it touches the dial itself only at the moment of noon on the summer solstice, which is when the sun is highest in the sky at any location.