Sensitivity analysis and quality assessment of laboratory BRDF data
A detailed quality and sensitivity analysis of hyperspectral bidirectional reflectance distribution function (BRDF) data, acquired under controlled laboratory conditions at the European Goniometric Facility of the Joint Research Center, Ispra/Italy, has been performed. In regard to bidirectional reflectance measurements in the field with the FIGOS goniometer, the impact of angular data sampling, the movement of the sun, and the Lambertian assumption of a Spectralon panel have been analysed. An erectophile grass lawn canopy and a planophile watercress surface were chosen as main targets. A GER-3700 spectroradiometer providing hyperspectral resolution was used to analyse the wavelength-dependency of the effects. The results of the sensitivity analysis show that in a first step a moderate resolution of 15 degrees and 30 degrees in zenith and azimuth, respectively, is adequate to capture the BRDF of vegetated targets. Only in the hot spot area a higher resolution is desirable. The movement of the light source during data acquisition is found to be critical, and should be kept within ±1 degree of the source zenith angle in order to obtain homologous BRDF data sets.
Bibliographic Reference: Article: Remote Sensing of the Environment
Record Number: 199810502 / Last updated on: 1998-05-05
Original language: en
Available languages: en