When imaging over long horizontal paths it is often the case that the isoplanatic patch size is on the order of, or smaller than, the diffraction-limited sampling rate of the imaging system. In these scenarios it is also common for the atmospheric Fried parameter to be only slightly smaller than aperture size. If the integrated turbulence strength is relatively low the main effect of the turbulence volume is to introduce shift-variant tip and tilt distortions to what is otherwise clear image. I refer to this condition as extreme anisoplanatism. In this talk, I will outline a theory for this anisoplanatic image formation following a light-field approach. Also, I will provide some insights into the performance of some image recovery techniques in the presence of extreme anisoplanatism. Finally, I will suggest how angular diversity may be used as a technique for improving scene recovery in these conditions.
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