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Old 09-06-2019, 11:46 AM
Wavytone
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Wavytone is offline
 
Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
Better than solar noon:

1. Use a plumb-bob on a string for an accurate vertical, with the string casting a shadow. Push a toothpick through the string near the top, to provide a reference point (at step 3). Plumb-bob suspended over a point marked on the ground (nail will do fine).

2. Choose a few pairs of times say 1:30, 2, 2:30 and 3 hours before and after solar noon, so the string will cast a longer shadow.

3. At each of the times before and after solar noon, mark where the reference point in the string falls (ie the intersection of string and toothpick).

4. Pull out a tape measure and subdivide the pairs using a tape measure. The midpoints lie on the north-south axis, as does the tip of the plumb-bob.
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