Dear Fernando, I also try to give you some suggestion for your sundial that contemporarily " has to be vertical" to be seen comfortably and " has to be horizontal" to have the possibility to work during the whole year .
For me a type of sundial that can satisfy both conditions is a reflection sundial with a tilted - almost horizontal - small mirror (always enlightened from the sun) and with the lines drawn on a vertical plane . The project is not difficult enough and, if you succeed in understand the Italian language, I can send a program - written by me - to make the calculation (or I can make them for you) The program has several possibilities included that to look for the approximate orientation of the mirror, a program to help to fix the mirror with the wanted angles and one for the search of the same angles after having fixed it. I've tried to calculate a sundial with Solar Local Time with the Latitude of Brasilia with a vertical plane (wall) facing South and a mirror tilted of 35 degrees. I attach an image of the result. The mirror is distant 100 from the plane and the rectangle is 600 x 500 (it's an example) If you want the wall facing North the mirror has to be tilted 15 d. (in the opposite direction) Best wishes Gianni ------------------------------------------ Ing. Gianni Ferrari Via Valdrighi, 135 41100 - MODENA ( ITALY ) EMail : [EMAIL PROTECTED] http://members.tripod.com/meridiane/index.htm Attachment converted: MAC Hard Disk:Brasilia.JPG (JPEG/JVWR) (000196D3)
