Total Sky Imager

Image of the sky at the sunset.
Thin clouds are visible.
In July 2003 a Total Sky Imager (TSI, model 440A) has been installed on the roof of the ENEA Station at Lampedusa. The TSI has been designed to automatically monitor the cloud conditions; it records images of the sky under a wide field of view, by means of a CCD. The collected images are analyzed to derive the fractional cloud cover in nearly real time.
The main components of the TSI are: a rotating hemispheric mirror provided of a shadowband, a downward looking CCD, and acquisition electronics. The shadowband prevents that direct solar light is reflected from the mirror on the CCD