These plots define the normalized ratio or error of the measured angular response to ideal(cosine) response for each channel for each shadowband instrument. This radiometric characterization is made along two orthogonal planes (-90 to +90 south-north and -90 to +90 west-east) of the diffuser. The UV-MFRSR foreoptic is designed for near-perfect angular response, and the Lambertian response of these instruments has been described by Harrison et al. (1994) and Michalsky et al. (1995). These angular corrections are applied to the direct-beam measurement, and also to the diffuse measurement assuming isotropic sky irradiance, then these corrected direct and diffuse values are added to get a revised total horizontal value. The designations SNnnn and WEnnn refer to the azimuthal scan direction from south to north or from west to east. The nnn designates the nominal center wavelength of the filter band pass.


Graphs of the data are available. Enter a date, and it will find the cosine correction data for the time closest to and earlier than the date selected.