Hi Gianni: Thanks so much for all the thought you put into solving the gnomon height problem and the work you did to actually produce drawings of my azimuthal dial with the ring order I suggested.
Looking at the drawings and reading your explanation of them leads me to believe that you have made an error. Fer confirmed my suspicion that the hour lines of one month cannot be connected to the hour lines of the adjacent if the months are not in their normal order. Look at it this way: Take an azimuthal dial from Fer's Spin program make a hard copy and cut out all the rings with a scissors (hard to do in practice, so just imagine it). Copy each of the rings on a xerox, increasing or decreasing the radius size of each so that the inner month ring (June) is the smallest and the outer month (December) is the largest. Now paste them all back together in the desired new sequence. Now you can imagine what the face would look like. Each ring would have 1/12 th of each time line which absolutely would NOT be connected to the line in the adjacent rings. Also, there would be 12 rings instead of the 11 rings shown on your drawings. Does this make sense? Sometimes I wish I had a scanner so that I could make and send little hand-made drawings of what I'm talking about. A picture is worth a thousand words! Thanks Gianni, John C. >Hi John , >if in an azimuthal sundial we take the circles as you propose we get for >every month a point. >If we connect these points we get some hour lines (Standard or Mean Time ) >that have the shape that you can see in the two figures attached. >In the pictures the lines are made by segments and are not smoothed but a >better result is gotten taking a point (a circle) every 15 days. > >In the pictures the radii are 20 cm for June, 30 for July, 40 for May, 50 >for August, 60 for April, 70 for Sept, 80 for March, 90 for Oct, 100 for >Feb, 110 for Nov, 120 for Jan and 130 for December. The pole is high 150 >cm >In the second image I have tilted the pole toward North to form an angle of >60 degrees with the horizontal plane. >The figures have been gotten with my program SUND98P distributed with the >issue of September 1998 of The Compendium. > >The curves are very condensed in summer : I would have to make some other >test to get good results aesthetically > >Best > >Gianni Ferrari > > > >--------------------------------------------------------------------------- >Ing.Gianni Ferrari >Via Valdrighi, 135 >41100 - MODENA (ITALY) >EMail : [EMAIL PROTECTED] >http://members.tripod.com/meridiane/index.htm >--------------------------------------------------------------------------- > > >Attachment Converted: C:\STARNET\EUDORA\AZIMUTH1.GIF > >Attachment Converted: C:\STARNET\EUDORA\AZIMUTH2.GIF >
