  The OmegaCAM wide-field optical imager is the sole instrument on the VLT
Survey Telescope at ESO's Paranal Observatory. The instrument, as well as the
telescope, have been designed for surveys with very good, natural
seeing-limited image quality over a 1 square degree field. OmegaCAM was
commissioned in 2011 and has been observing three ESO Public Surveys in
parallel since October 15, 2011. We use the Astro-WISE information system to
monitor the calibration of the observatory and to produce the Kilo Degree
Survey (KiDS).
  Here we describe the photometric monitoring procedures in Astro-WISE and give
a first impression of OmegaCAM's photometric behavior as a function of time.
The long-term monitoring of the observatory goes hand in hand with the KiDS
survey production in Astro-WISE. KiDS is observed under partially
non-photometric conditions. Based on the first year of OmegaCAM operations it
is expected that a $\sim 1%-2%$ photometric homogeneity will be achieved for
KiDS.
