Article

Sun Compass

We all know the sun rises in the east and sets in the west, and around midday it's at its highest. As photographers we often want to be more precise, like when will it rise and set and at what angle, also where will it be in the sky both by compass position and height at each part of the day.

The objective beyond sunrise and sunset photos is to be able to work out where shadows will fall, when some features are best photographed, and to avoid the sun in the lens.

In some cases the requirements will be more complex, perhaps we want to know when the sun will come between some trees, or will light the tunnel of a burial chamber.

We can get this information for any date and time from computer programs, but as we don't always want to carry our computers with us, we have transportable 'tools' we know as a sun compass.

The major difference between the computer program and sun compass is that the computer program is complex and you need to give it quite a lot of information, while the sun compass is slightly generalised, and accurate enough for what we need, within the constraints we operate, as long as we understand what it is doing and represents.

There are several designs of sun compass including:-

• Small compass on a mountboard with markings
• Map overlay or card/paper sheet
• Data table that you use with an ordinary compass

I have, and use all of these, and here we are going to explore what they have to offer and with some give you the information to print or create your own.

Small compass on a mountboard with markings

The advantage is that it is self contained, you don't need a map, compass, anything else. It shows you where the sun will rise and set for each month of the year. The reverse shows the angle at midday for each month. You don't have the detail of where the sun will be precisely as the day goes on but have to guess this.

Map overlay or card/paper sheet

Aligned to the map north, or with a compass, different designs show slightly different information. The one I use has rise and set and position of the sun at each hour of the day. As I carry this and the one above, I often use them together.

The overlay being used on a map may allow you to plan the best time of day to first visit locations.

Data  table that you use with an ordinary compass

This is the numeric equivalent to the above and using an ordinary compass you can locate quite accurate positions. You can also use the compass on a map as above. These tables could be as specific as you wanted, being computed for a specific location and date, or could be more general, perhaps approaching being the same as the aids above.