>>3609264Well, that depends on if the guy was crouching while taking the photo, the only thing for sure is the horizon line shouldn't be further above the hat point, as you can clearly see the bottom plane. I used the window lines pointing at the horizon line to make a guess of where it should be, if any it may be lower if the walls are properly aligned.
>>3609303That holds true only if you where aiming in said direction, and even then it's difficult that a person put himself in an angle of view (basically because we would lose balance rather easily), although you can make the point you'd still get an angle by moving your torso or crouching in some sort of angle, on a slope, however, id make the guess you'd try to compensate it by adjusting the ball of your feet. Regardless, if things are horizontally aligned they'd still point towards a horizon line, that's why you can still see things pointing towards it even if there's a taller building, slopes or mountains blocking the view, no tilt, not even your own (unless it's on a 90º angle) should affect this.
Cameras use distortion (don't know about old cameras or cameras in general so take that as you will) so they could exaggerate perspective, making it difficult to have an accurate representation of what is really going on on the image.