A focal plane array having: a plurality of detectors; a plurality of unit cell sections, each section being fed by charge produced by corresponding detector for producing a sequence of frames; and a plurality of sets of storage sections, each section being coupled to a corresponding one of the unit cells. Each set of storage sections includes a plurality of storage units for sequentially storing the frames. A region of interest selector section examines the frames of the plurality of unit cells, to detect at least one of the frames having a predetermined characteristic. A processor: (i) identifies a sub-set of the plurality of unit cells proximate the detected unit cells having the predetermined characteristic to establish a region of interest; and (ii) sequentially reads the plurality of storage units in the storage sections coupled to the sub-set of unit cells in the established region of interest.