Dear Roger, beeing right before installing such a sundial on a nearby shoolground I am very interested in your excel sheet and would be happy receiving a copy via eMail.
Thanks to all of this list who helped me up to now with this project. Best regards Ulrich =========================================== Ulrich Dörschel (Doerschel) Fasanenweg 7, D-56235 Ransbach-Baumbach ------------------------------------------- Tel.privat: (+49) (0)2623-807197 eMail.privat: [EMAIL PROTECTED] eMail.office: [EMAIL PROTECTED] =========================================== 50d 28m (north), 7d 43m (east) =========================================== Roger Bailey wrote (08. Apr 1999): > Dear Don Christensen, > > I am pleased that your question on analammatic dials has been answered > well. Tom McHugh offered the basic facts, Fer de Vries the mathematics, and > Mac Oglesby a design program. In the spirit of international intellectual > cooperation (competition?), I would like to match their offers and raise > the stakes but adding declination lines! > > In designing an interactive analemmatic sundial for the Calgary Science > Center, I discovered the important the length of the shadow. The best user > experience is achieved when the tip of their shadow intercepts the > elliptical ring of hour markers. This shadow length varies with the > latitude, solar declination, (seasons), time of day and height of the > users. I rewrote an old program for analemmatic dial design as an Excel > spreadsheet including tabular and graphical output of the usual X,Y > coordinates on the ellipse for the hour markers and the Zodiac (where you > stand) on the Y axis. I have now added to the graphical output, plots of > declination lines defining the path of the tip of the shadow as a function > of solar declination (date), dial size and gnomon height. > > Not only is it a great design tool but it allows the user to experiment > with the input variables: latitude (including southern hemisphere as > negative numbers), longitude correction options, declination, gnomon > height, major axis size, etc. It taught me a lot about this type of dial > and I would be happy to share it. > > If you can read and use Excel .xls files, I will send it out as an e-mail > attachment to those that reply to this message. The usual freeware > copyright, disclaimers and restrictions on commercial use apply. For those > who received an earlier version, please replace it with this update. The > original had significant errors and limitations. > > Roger Bailey > Walking Shadow Designs, > N 51 W 115 > where I am amazed at what you can accomplish if you unplug your television. >
