Modeling geophysical properties of the Algodones Dunes from field and laboratory hyperspectral goniometer measurements using GRIT and comparison with G-LiHT imagery

Modeling and intercomparison of field and laboratory hyperspectral goniometer measurements with G-LiHT imagery of the Algodones Dunes

“…In order to avoid this pitfall, we have taken a different approach, building upon an earlier workflow that we previously developed. 6 We have added some important refinements, which allow the approach to be more successful. Another variation of this approach, which we will introduce later, takes advantage of the explicit form of the SHOE width found in Eq.…”

“…In that initial exploration, 6 we inverted the Hapke IMSA solution solving Eq. (1) for the product of the single particle phase function and the SHOE correction E Q -T A R G E T ; t e m p : i n t r a l i n k -; e 0 0 6 ; 1 1 6 …”

“…Due to time limitations, our measurements were collected from six locations using the goniometer of the Rochester Institute of Technology (GRIT). 5,6 The GRIT positioned the fiber optic of an ASD spectrometer with 5 deg fore-optic over a set of hemispherical positions between 0 deg and 65 deg in zenith and 0 deg and 360 deg in azimuth.…”

“…For the laboratory studies, BRDF measurements were conducted using two different generations of the goniometer system, GRIT 5,6 and GRIT-T. 9 In a laboratory setting, BRDF measurements are sometimes referred to as BCRF 7,8,10 measurements when there is a finite aperture for both the single directional illumination source and the sensor. The term "factor" signifies the referencing of sample radiance data to the radiance of a Lambertian standard.…”

Fully automated laboratory and field-portable goniometer used for performing accurate and precise multiangular reflectance measurements

“…The primary purpose of the system is to estimate the biconical reflectance factor (BCRF) and hemispherical-conical reflectance factor (HCRF) [2][3][4] of various soils and short vegetation to better understand the limits of existing radiative transfer models, to validate modified radiative transfer models, 5,6 and to aid in the vicarious calibration of remote sensing platforms. 7 Reflectance factors are calculated by comparing the radiance of a target surface to that of a Lambertian standard reference. [2][3][4] Specifically, *Address all correspondence to: Justin D. Harms, E-mail: jdh1069@rit.edu a reflectance factor RF is estimated from the ratio of the radiance L r reflected from the surface to the radiance L ref reflected from a Spectralon reference panel.…”