... As stable VLT work horses during the past 8 years obviously the two FORSes have in many ways also been instrumental to the definition of the VLT queue observing paradigm which includes both systematic collection of calibration data, online and offline reduction pipelines. The original concept for the photometric calibration and the FORS imaging pipelines involved acquisition of simple twilight images which were used for flatfielding, and observation of Landolt photometric standards. ...