Point spread functions for mapping artificial night sky luminance over large territories

Knowledge of the night sky radiance over a large territory may be valuable informationto identify sites appropriate to astronomical observations or for assessing impacts ofartificial light at on ecosystems. Measuring can complex endeavourdepending desired temporal and spatial resolution. Similarly, modelling artificialnight multiple points represent significant amount ofcomputing time depending complexity model used. The use convolutionof point spread function with sources geographical distribution has been suggestedin order territories hundreds kilometres in size.We determine how is sensitive main driving parameters ofthe artificial such as wavelength, ground reflectance, obstaclesproperties, Upward Light Output Ratio Aerosol Optical Depth using Illuminav2 model. obtained functions were used brightness Mont-M\'egantic International Dark Sky Reserve winter summer conditions. Theresults compared New world atlas brightness, situ Quality Camera measurements. We found that atlasoverestimates by 55% whereas Illumina underestimatesit 48%. This due varying atmospherical conditions fact modelonly accounts public sources.