[photogrammetry, standards]
In imagery, a type of geometric distortion where objects appear to be displaced radially outward or inward from the image center (or principal point). Radial displacement can be caused by elevation differences in the terrain or by lens distortion, creating the illusion that tall objects—such as buildings, towers, and trees—lean away from the center at a ratio proportional to their height. The taller the object or the greater its distance from the image center, the more significant the displacement. Radial displacement is often referred to as building lean.