Hello Tracy, Sorry for jumping in so late.
You like to have an analemma associated with the date line? There is a nice way, introduced by Marinus Hagen, founding father of the Dutch Sundial Society. See the small attached figure. One should stand right on the date line, as explained before. The analemma has a scale along the E-W axis, from which the EoT correction can be read. The large ticks are at 5 minute intervals. This is in fact an alternative for the use of a table or a separate EoT graph. Best regards, Frans Maes ----- Original Message ----- From: "Tracy Paine" <[EMAIL PROTECTED]> To: "sundial list" <sundial@uni-koeln.de> Sent: Sunday, October 29, 2006 10:52 PM Subject: date scale Hello Everyone I really like the drawing you made John for your customers - it helps a lot. Thank you. Thanks Tony for the picts and Powerpoint presentation - it is wonderful. Thanks Chi-Lian and Linda for your comments. After reading the advice I have received, I think that I will make my date scale the conventional way - although I think the analemma looks way cooler! It looks as if the first day of summer and the first day of winter are at each end of the scale. Is this true always? Also, does one stand directly on the centerline, or on the month "block" which falls to the left and right of the center line? More on my previous obsession of using the figure 8 in the date scale: If I am not mistaken, an analemma, on the ground for instance, can be made by marking the position of the sun (cast by some point) at the same time for a year every few days or so. I am referring to the website: http://www.cerrilloshills.org/analemma/path3.htm So, if I were to mark the path at noon, local time, for a year, the figure 8 should fall on the N-S line? It appears as though the months outlined on the figure 8 match the date scale in placement except at the top portion of the figure 8 where the months seem to flip from the left side to the right side. I can't help but think that the straight line date scale mimics the analemma in month placement. That's why I figured that I would make the figure 8 instead of the plane straight line. Also, I thought about positioning some type of gnomon that would cast a bright spot (or shadow) on the date scale which could follow the figure 8 path exactly (at noon) just like the noon analemma sundial featured in the website above. I am fascinated by the analemma and would love to somehow use it in my sundial, however, I definitely want my sundial to be correct and accurate - no false sundials here! But I keep seeing the analemma used as a date scale in pictures on the internet. One I found looks like it is bronze. If I shouldn't use the analemma in the date scale, where could I put it in the sundial properly? Or, should I just make a separate noon analemma sundial like that in the website referred above? ---------------------------------------------------------------------------- ---- > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > >
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