A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Richard M Pisko
Date: 2003 Aug 12, 01:43 -0600
On Sun, 10 Aug 2003 19:41:20 -0700, Brooke Clarke wrote: >It's about 15 feel long and a few feet wide as far as I can remember. >Where the hole is at the base of the skylight might be above the floor >by 12 -15 feet. >In the winter when the slant distance is long the image is dim so the >white 3x5 card makes it visible. >I tried a number of different hole sizes. It's like a f-100 lens and >you get an image of the sun on the floor. As the hole gets larger the >image gets brighter and fuzzier. > Thank you, good information. I do have an old book that I still like "Sundials -- Their Theory and Construction" by Albert E. Waugh; but I am glad to get more accurate and newer ideas. -- Richard ...