Quality and homogeneity of the Level 0 data stored in the archive. Top panel: pie chart of the IBIS-A data divided for the median value of the quality image parameter q (in arcsec) during acquisition of Level 0 data (see Sect. 3.1 for details). Bottom panel: number of Level 0 datasets depending on their duration d and homogeneity of the quality image parameter q during observations. The homogeneity of the dataset is described by the standard deviation of the q values measured during the observing run.