Please take a look at the Powell and Dillard photos of the face of the TSBD ( they are posted in the thread " Are These Photos Legit"
The horizontal shadow being cast by the window above BRW head tells us which photo ( Dillard or Powell ) was taken first....
The table shows the sun position from 12:20-12:40. Azimuth changes almost 6 degrees over this short time span, while altitude changes very little. The animation simulates a view similar to Powell’s view. There is no noticeable change in the window shadow over this time period. I don’t know why there is an apparent difference between Dillard and Powell, but it is not due to sun position the best I can tell.
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