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Author Duriscoe, D.M.; Luginbuhl, C.B.; Moore, C.W.
Title Measuring Night-Sky Brightness with a Wide-Field CCD Camera Type Journal Article
Year 2007 Publication Publications of the Astronomical Society of the Pacific Abbreviated Journal Publ Astron Soc Pac
Volume 119 Issue 852 Pages 192-213
Keywords light pollution; light at night; skyglow; monitoring; measurement; CCD
Abstract We describe a system for rapidly measuring the brightness of the night sky using a mosaic of CCD images obtained with a low-cost automated system. The portable system produces millions of independent photometric measurements covering the entire sky, enabling the detailed characterization of natural sky conditions and light domes produced by cities. The measurements are calibrated using images of standard stars contained within the raw data, producing results closely tracking the Johnson V astronomical standard. The National Park Service has collected hundreds of data sets at numerous parks since 2001 and is using these data for the protection and monitoring of the night-sky visual resource. This system also allows comprehensive characterization of sky conditions at astronomical observatories. We explore photometric issues raised by the broadband measurement of the complex and variable night-sky spectrum, and potential indices of night-sky quality.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6280 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 193
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Author Fiorentin, P.; Boscaro, F.
Title A method for measuring the light output of video advertising reproduced by LED billboards Type Journal Article
Year 2019 Publication Measurement Abbreviated Journal Measurement
Volume 138 Issue Pages 25-33
Keywords Lighting; Energy; Instrumentation; Planning; Light-emitting diode displays; Photometry; Video recording; Image analysis; CCD image sensors; Luminance; Glare
Abstract Improving knowledge of the light output of digital billboards is important to better assess their effect on driver distraction when they are installed along roads. In this work the emission of an LED based billboard is measured when playing advertising video-clips. In particular the average and the maximum values of the luminance are evaluated. The same video-clips are also analyzed when shown on an LCD monitor, aiming at separating the variability of the videos and of the playing device. The results allow to evaluate an utilization factor of the billboard: the videos have an average luminance around 11% and a peak luminance of 35% of the maximum luminance obtainable from the billboard. The power consumption of the billboard is measured, aside the photometric analysis. The luminance of the device are found linearly dependent on both the power and the effective current absorbed by the device from the grid, with a discrepancy within 6%. It could be a useful information for billboard manufacturers to qualify their product when they do not own photometric instruments.
Address Department of Industrial Engineering, University of Padova, Padova, Italy; pietro.fiorentin(at)unipd.it
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0263-2241 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2214
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