Sun Position and Cloud Effects on Reflectance and Vegetation Indices of Corn

  title={Sun Position and Cloud Effects on Reflectance and Vegetation Indices of Corn},
  author={Eduardo Godoy de Souza and Peter C. Scharf and Kenneth A. Sudduth},
  journal={Agronomy Journal},
The reflectance characteristics of plants and plant canopies far from solar noon (i.e., at large solar zenith angles) or with cloudy skies are not well known. This is an obstacle to making real-time, variable-rate N fertilizer applications based on canopy reflectance because such a system must work under cloudy skies and at all times of day. Our objective was to develop spectral radiometer reflectance corrections for variations in incoming sunlight so that the same reflectance reading would be… 

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