This file consists of three rows and the same number of groups as the Science Image file. The first row contains the histogram of the pixel values in the Science Image file. The second row contains the histogram following the AtoD correction step. The third row contains the histogram of the Calibrated Science Image file values. The creation of this file is controlled by the keyword DOHISTOS in the input science image header. Only those pixels flagged as good in the DQF are included in the histograms. The Calibrated Science Image Histograms file is identified by the extensions ``.C2H'' and ``.C2D''.
