Abstract
Operations of the first ESO Very Large Telescope (VLT), the 8m-Antu, started on April 01, 1999, and two instruments, FORS1 (FOcal Reducer/low dispersion Spectrograph) and ISAAC (Infrared Spectrometer And Array Camera) became available to the user community on the same day. ESO's Data Flow Concept embraces the definition of observations (Phase 2 Proposal Preparation, P2PP), the execution (Paranal Science Operations), and the different functions of Data Flow Operations (DFO). As part of DFO, the Quality Control Scientists are in control of the following tasks: (1) distribution of data, (2) creation of master calibration data, (3) reduction of science data, (4) performance of quality control and trend analysis. In this paper we will describe in more detail the work within the Quality Control Group, with particular emphasis on the different methodologies applied to the two instruments, and give the insider point of view on operations with a large telescope after almost one year of experience.
