Quality Control and
Data Processing

The HAWK-I calibration scheme is typical for imaging instruments. A complete set of calibrations consist of a set of bias and twilight flatfield frames. The bias frames are processed by the pipeline in an 'elementary' way, without other calibration products involved. The twilight flats are processed next, with a master bias required as input. Further, standard star observations are processed utilizing master bias and master twilight flat. Processed standard star data in different, BB filters are provided to users as indication of photometric conditions during the night. The photometric and astrometric calibration of the science data is done independently right on the data using input 2MASS catalogue. In quick-look mode on Paranal, the HAWK-I pipeline has a fixed set of calibration products which are all static. Hence these dependencies cannot be properly respected. The calibration solutions processed by QC Garching do respect the cascade. Together with quality checking, this results in the optimum possible products, meaning that any instrumental and ambient influence on the science data is monitored and removed by the calibration products in the best possible way. These master calibrations are archived and can be downloaded using the calSelector service.