Remote visibility measurement technique using object plane data from digital image sensors

Atmospheric visibility sensors in use today suffer from several deficiencies. These result from measurement errors made by either a human observer or by inferring visibility from measurements made over a small volume under (typically) artificial lighting using a transmissometer or forward-scattering instrument. This paper reviews the basic theory for establishing visibility measures and relates those to common image analysis parameters. A visibility sensor approach is described that utilizes a digital camera and image analysis methodology to provide a potentially more accurate visibility measure. System concept and several illustrative examples are presented