You should enter as much information as possible into the Inputs section, then click on the Calculate button. The calculation results will then appear in the Outputs section.

Here is a list of inputs and how to use them:

Latitude
Your latitude, in degrees North or South of the equator (use the pull-down menu after the input field to indicate which one). You may use either decimal or degree-minute-second (DMS) notation for latitude. For decimal values, enter the latitude simply as, for instance, "45.5" (don't include the quotation marks). For DMS values, enter the degrees followed by "d", arc-minutes followed by "m", and arc-seconds followed by "s". Do not use spaces. A sample DMS value would be "45d30m0s". This is a new feature of SunAngle, so please let me know if you have any questions about it.

Longitude
Your longitude, in degrees East or West (use the pull-down menu after the input field to indicate which one). You may use decimal or degree-minute-second notation for longitude; please see the instructions for latitude above for more information.

Date
Indicate the month and date using the pull-down menus.

Year
Indicate the year using the pull-down menu. If the year you are interested in does not appear, select any value (the exact year matters very little for most calculations...this variable only affects the equation of time value, and only by a few seconds here and there).

Elevation
Your elevation compared to the surrounding terrain, in meters or feet (use the pull-down menu after the input field to indicate which one). This is not the same as your elevation above sea level; it's your height above (or below) the land and geographical features in your vicinity. So if you're on a hill, your elevation is the height of the hill. If you're on a mountain and you're surrounded by other mountains of the same height, your relative elevation would be zero. This input is only necessary for computing accurate values for the times of sunrise and sunset, so you can leave this set to the default value of "0" if you don't know your elevation or if you're not interested in extremely accurate sunrise/set outputs.

Time
Indicate the time you are interested in calculating sun angles for, using "12:34" or "1234" notation. You can indicate morning (AM), afternoon (PM), or 24-hour time using the pull-down menu to the right of the text field. 12:00 AM is considered to be midnight, and 12:00 PM is noon (it's best to actually avoid these confusing cases and use 11:59 or 12:01 to be safe). Note: pay special attention to the AM/PM/24 indicator...it's a common error to forget to set this correctly.

Time Zone
Select the time zone which includes the location you're interested. There are 36 time zones in the menu, all specified by a standard letter designation and the time difference from Greenwich Mean Time (GMT) when daylight savings time is not active. If you are unsure of your time zone, you can look it up. The program checks to see if the time zone you selected is anywhere near the longitude of your location...if they're too far apart it will alert you.

Time Basis
The time you enter in the Time input field can be either clock time or local solar time (LSOT). Clock time, which is the default value of this input, is the time you'd observe on any time keeping device. Solar time is a system based more exactly on the cycle of the sun...it differs from clock time since the latter standardizes time to suit the practical needs of modern society.

Daylight Savings
Daylight savings time (DST) is observed in most locations around the world by setting clocks ahead one hour during the summer. If DST is in effect on the date you're investigating, set the Daylight savings input to Yes. I'll be adding a chart of DST information soon; in the meantime the TimePalette program (also shareware) has a great deal of DST information.

When you've entered all of the inputs, click on the Calculate button, and the results will appear in the Outputs section immediately.

Note that you can click on the labels of any input or output field to learn more about it.