Capricorn: Dec.22-Jan.29 The Sundial Primer
created by Carl Sabanski
Capricorn: Dec.22-Jan.29

The Sundial Primer Index

SONNE Features - Helmut Sonderegger

SONNE has available to the user additional features that you will find very useful. Figure 1 shows the opening screen when the software is started. At the top a drop-down menu can be accessed by selecting "Calculations". There are a number of very useful utilities including:
  • Sun Rise and Set (F9)
  • Position of Sun (F10)
  • Time for given Sun Position (F11)
  • Sun: Equation of Time and Declination (F12)
  • Graph of the Equation of Time (Alt+F12)

The shortcut keys provided above can be used to quickly access any of these features. 

Figure 1: SONNE Features

Figure 1: SONNE Features

The default data used is obtained from the entries made in "Options:: Reference Year and Location (F5)". The default month and day are taken from the system clock. All the calculated information and tables can be printed.

IMPORTANT: All calculated times are "Standard Time" and do not correct for "Daylight Saving Time".

Sun Rise and Set (F9)

This feature will determine the times of sunrise and sunset for any location and on any date. Figure 2 shows the dialogue box that appears. The "Input" data can be changed and the type of "Twilight" to be determined can be selected. Selecting the "Evaluation" button will result in the calculations being performed and the following information is provided:

  • Sun Rise
  • Sun Set
  • Moon Rise
  • Moon Set
  • Twilight: Beginning & End
  • Declination (Sun)
  • Equation of Time

Figure 2: SONNE Features - "Sun Rise and Set" (F9)

Figure 2: SONNE Features - "Sun Rise and Set" (F9)

This information can be pinted.

As a result of atmospheric refraction and the fact that the sun's diameter is approximately 0.5, sunrise and sunset are determined when the sun's elevation is 0.83 below the horizon.

The various types of "Twilight" are defined as follow:

"Civil Twilight": the sun's elevation is between 0 50" and 6 below the horizon.

"Nautical Twilight": the sun's elevation is between 6 and 12 below the horizon.

"Astronomical Twilight": the sun's elevation is between 12 and 18 below the horizon.

Selecting the "Table" button will result in a table with all the information available in Figure 2 but for every day of the entered month. To have the table start from the first of the month be sure to enter the value of "1" for the "Day" or else the table will start from the entered day. Table for other months can be produced by changing the value for the "Month". Figure 3 shows this table.

Figure 3: SONNE Features: "Sun Rise and Set" Table

Figure 3: SONNE Features: "Sun Rise and Set" Table

The table can be printed or saved as a text "TXT or an Excel "CSV" file.

Position of Sun (F10)

This feature will determine the co-ordinates of the sun at any location and on any date and time. Figure 4 shows the dialogue box that appears. The "Input" data can be changed to any location and date. The "Time for given Sun position" must also be entered. Selecting the "Evaluation" button will result in the calculations being performed and the following information is provided:

  • Sun's Altitude
  • Sun's Azimuth
  • Sun's Declination
  • Equation of Time

Figure 4: SONNE Features - "Position of Sun" (F10)

Figure 4: SONNE Features - "Position of Sun" (F10)

This information can be printed.

Time for given Sun Position (F11)

This feature will determine the time the sun reaches a given azimuth at any location and on any date. Figure 5 shows the dialogue box that appears. The "Input" data can be changed to any location and date. The "Evaluate Time for this Particular Azimuth of Sun" must also be entered. Selecting the "Evaluation" button will result in the calculations being performed and the following information is provided:

  • Sun position is reached at (time)

  • Altitude of Sun

Figure 5: SONNE Features - "Time for given Sun Position" (F11)

Figure 5: SONNE Features - "Time for given Sun Position" (F11)

This information can be printed.

Sun: Equation of Time and Declination (F12)

This feature will determine the values of the Equation of Time and the sun's declination at any location and on any date. Figure 6 shows the dialogue box that appears. The "Input" data can be changed to any location and date. Selecting the "Evaluation" button will result in the calculations being performed and the following information is provided:

  • Declination (sun)

  • Equation of Time

Figure 6: SONNE Features - "Sun: Equation of Time and Declination" (F12)

Figure 6: SONNE Features - "Sun: Equation of Time and Declination" (F12)

This information can be printed. Selecting the "Show Tables" button will result in tables with all the information for an entire year being available. Four tables can be displayed as shown in Figure 7. They are selected by picking the desired button at the bottom of the screen and include:

  • Equation of Time (EoT)

  • EoT + Longitude Corr: includes longitude correction

  • Sun Declination

  • Sun passage times: time of the meridian line passage of the sun at solar noon

Figure 7: SONNE Features - "Sun: Equation of Time and Declination" Tables

Figure 7: SONNE Features - "Sun: Equation of Time and Declination" Tables

Selecting the "EoT in Graphic" button will display a graph of the Equation of Time as shown in Figure 8. There is a choice to "include longitude correction" in the graph and if chosen the graph will be changed. The graph can be printed or saved as an "HPGL" or "DXF" file. The insert shows the dialogue box that appears when the "Save as dxf" button is selected. This same box appears if the "Save as hpgl" button is selected. There are a number of choices that can be made before saving the file.

  • "Scaling-factor in Direction y-axis": allows the graph to be extended or compressed along the vertical or Y axis.

  • "Mirror Graph along x-Axis": will invert the graph along the horizontal or X axis. This will result in the "Sun is fast" values to be negative and the "Sun is late" values to be positive.

  • "show EoT with additional longitude correction...etc": will include longitude correction in the EoT graph. If "include longitude correction" was selected in the previous screen this box will already be checked.

Figure 8: SONNE Features - "Sun: Equation of Time and Declination" Graph

Figure 8: SONNE Features - "Sun: Equation of Time and Declination" Graph

Graph of the Equation of Time (Alt+F12)

This feature will go directly to the graph shown in Figure 8.