Orateur
Dr
Dusan Mandat
(Institute of Physics of Academy of Science of The Czech Republic)
Description
The All Sky Camera (ASC) was developed as an universal device for a
monitoring of the night sky quality and night sky background
measurement. ACS system consists of an astronomical CCD camera, a fish
eye lens, a control computer and associated electronics.
The measurement is carried out during astronomical twilight. The
analysis results are the cloud fraction (the percentage of the sky
covered by clouds), night sky brightness (in mag/arcsec2) and light
background in the field of view of UHECR instruments.
The analysis of the cloud fraction is based on the astrometry
(comparison to catalogue positions) of the observed stars, the algorithm
for derivation of the night sky brightness, and examples of obtained
results.
The instrument is used within Pierre Auger Collaboration and CTA Site
Selection Work Package.
ASC camera consists of MII G1-2000 camera Moravian Instruments), Fujinon
objective YV2.2x1.4A-SA2 and electronics.
Original picture resolution is 2 Mpix – 16 bit depth, monochrome
The algorithm to calculate the cloud fraction compares the stars found
in the image and their visible counterparts from a star catalogue
(angular distance is typically less than 0.5 degree).
The system is more versatile, it could generate cloud fraction of a
chosen sky region to drive a robotic telescope, measure the night sky
background of a chosen sky region calibrated to a custom instrument etc.
Auteur principal
Dr
Dusan Mandat
(Institute of Physics of Academy of Science of The Czech Republic)
Co-auteurs
Prof.
Miroslav Hrabovsky
(Joint Laboratory of Optics of Palacký University in Olomouc)
Dr
Miroslav Pech
(Institute of Physics of Academy of Science of The Czech Republic)
