This Excel spreadsheet allows rapid initial orientation of billboard objects and 3DS models, so that the billboard image or model is set up aimed precisely towards the Sun, with the top of the original image pointing towards celestial north.
The input data required are the right ascension and declination of the billboard object - these values can be entered in decimal degrees, or degrees, minutes and seconds. Right ascension can also be entered as decimal hours, or hours, minutes and seconds.
The spreadsheet then calculates the necessary Axis and Angle commands to orientate your billboard correctly - just copy the two lines from the spreadsheet and paste directly into your dsc file.
Note that pasting into WordPad causes the cell formatting codes to be included, not just the Axis and Angle text. Pasting into Notepad works as desired: only the words Axis, Angle and their numeric values are included.
The spreadsheet works correctly both with Microsoft Excel and when imported into Open Office.
Grant July 2003
Example dsc.xls spreadsheet
This Web page is maintained by Selden Ball
at Wilson Lab.
Please send any comments or corrections to firstname.lastname@example.org