Ok, that explains some of your confusion regarding concepts like lines of sight.
" But it's a photograph anyway so the landmarks you cross would not be the same as they would if you were actually there shooting a laser line across the landscape."
That doesn't make any sense. Do you believe the landmarks in the picture don't actually exist? They are in exactly the same spot on Google Earth.
"Foreshortening in the foreground of the photo changes the relative size of objects in terms of distance (or length as you measure from near to far)."
Again, this makes no sense. Who says there is "foreshortening"? And if there is, are you saying the objects are moved in the X or the Y axis?
"If you had a photo taken from directly above the landscape you could get a fairly accurate line if you had two identified points."
I identified three points and plotted them on the direct overhead imagery of Google Earth.
So, because it's almost impossible for me to lose my way in the deep woods you conclude that that is the root of my inability to understand a line of sight? I don't follow your logic on that.
That doesn't make any sense. Do you believe the landmarks in the picture don't actually exist? They are in exactly the same spot on Google Earth.
I'm pretty sure I explained that. The closer together two reference points are the more inexact the line of sight they form will be for a distant object. Since both reference points are very close together and are in the foreground of the pic there exact position when mentally transferred to an overhead view is distorted by the foreshortening caused by the long focal length of the lens being most accurate at its center. This is made very clear through a fisheye lens but the same thing occurs in any lens just to a lesser degree that's not noticeable.
Again, this makes no sense. Who says there is "foreshortening"? And if there is, are you saying the objects are moved in the X or the Y axis?
As explained above there is always foreshortening around the perimeters of a round lens. Objects viewed through that lens scattered through various areas of relative distortion and various distances from the lens are distorted to different degrees in their relationship to each other. When you don't even start from the center line of the image to project a sight line from the camera you are adding a significant error into an image that isn't perfectly rendered in the first place.
Add to that that camera's perspective is not horizontal to the objects you chose, it's several hundred feet above and we are looking down from the camera's actual aiming point at an angle that is not horizontal or vertical, and we don't have any accurate way of assessing whether a line between two objects you choose from the pic are a straight line back to the camera's location. Then you want to project that line out to 150+ miles from the camera.
I identified three points and plotted them on the direct overhead imagery of Google Earth.
Using some flawed techniques for choosing them.