Backdoc Posted 1 hour ago Author Posted 1 hour ago On 11/8/2025 at 2:32 PM, MIB said: I think that is true, however, judging the shadows is tricky because slight differences in position of the observer can change the perception of angle a great deal with no real way to remove the error that introduces. An analogy from algebra .. this is a situation of two variables, one equation. To get a precise answer you have to nail one of the variables down so it's a constant. To do that, you have to locate the observer's position precisely, within inches, else the ground slope, etc create uncertainty which means you cannot nail the time down precisely even if you know where the shadow is and what direction, relative to the observer (photo) it seems to be pointing. In just 20-30 minutes shadows change quite a bit. I was seated outside for lunch with too much sun on my face outside the large table umbrella. I put on sunglasses. In no time it seemed, my face was in the shade by the time the appetizer arrived. By the time my lunch arrived I was nearly fully in the shade. Just like Gimlin that day, I was not noting the exact times. It was just early afternoon lunchtime. Hard to know about Gimlin's statements as 30 min one way or another could make a diff on shadows. I remember Bill Munns showed this effect with a board in his book, "When Roger Met Patty" Assuming it got noticeably dark around 5pm or so. I'll accept whatever the best facts can tell us. If it's 2 pm great. If it is 3 pm fine by me. My hope is the high tech recreation made by Lazy Cowboy could help us determine this as well as many other facts. My hope was/is Lazy Cowboys recreation would act as an accurate sundial esp. matched up with the PGF images.
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