Stereo Imagery for long range

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Is it possible to measure distances and heights of objects that are far away over 1 km using Stereo technology ? If no, what is the limitation (in term of maximum range) of such a technology. In fact, I need to make a 3D scan of a big area (200m x 1000m) in order to detect all objects with predefined mininmum height and their coordinates using a UAV. Thanks