Small angle scattering by relatively large atmospheric cloud/fog water droplets and ice crystals can cause significant contrast reduction and blurring of imagery. While this effect is quite well explained and verified in field experiments and sensor models, the extent to which aerosols, especially those of quite prevalent anthropogenic fine/ultra-fine/coarse mode play a role in image degradation remains to this date, a controversial topic. In this work, the contribution of aerosols to image blur is revisited but with special focus on field data collected with a relatively large variety of ambient aerosol characterization and optical instrumentation. Ambient particulate/aerosol morphology and optical properties and trends are correlated with collected imagery using instruments including nano-class condensation particle counters, and a nephelometer. Images were captured by a visible camera at different times of the day over a 450 m path. We quantified the blurring in these images through evaluation of the Modulation Transfer Function (MTF). The MTF of the imaging system was characterized through a short-range experiment in the laboratory and turbulence MTF was computed independently from the turbulence-induced motion of features in the images. The aerosol MTF was extracted by dividing the overall MTF by the turbulence and imager MTFs.
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