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Figure 4: Differential imaging method applied to a meteor track. Left pane: original frame imaged by the FAVOR camera. Middle pane: image with the “average frame” (the mean values of each pixel over the last 100 frames), subtracted. There are residual signatures of stars due to higher level of fluctuations in the wings of star PSFs, as well as regions with very low fluctuation levels due to CCD defects and dust in the focal plane. Right pane: residual image divided by a “dispersion frame” (standard deviations for each pixels estimated over last 100 frames). The only significant deviations from the zero level are due to the fast transient, which may be located and extracted by a thresholding on a 3-4 level.