Hi Chris and All, Yesterday evening I was driving south on the interstate and saw a fabulous sunset where the sun was incredibly magnified...even before it got right down on the horizon. There were thin clouds that cut the light enough for me to observe the disk, and it sure did look wide. How would an apparently larger solar disk like that affect the gnomon/distance ratio and the shadow width characteristics on a tubular polar style, say, with the resultant shadow landing on the inside of an equinoctial ring where the receiving surface is parallel to the gnomon? The dark umbral part of the shadow would be diminished, right? I wonder if that effect should be factored in when choosing the ratio to use in determining the optimum diameter of a tubular gnomon?
Best, Jim Tallman www.artisanindustrials.com [EMAIL PROTECTED] 513-253-5497 --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
