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Robinson, B. F.

Publications and source records attributed to Robinson, B. F..

25 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Simulated response of a multispectral scanner over wheat as a function of wavelength and view/illumination directions

Oblique viewing sensors are to be launched in the late 1980's on the Multispectral Resource Sampler, being developed by the U.S. Since the resulting oblique measurements will need to be better understood, the reflectance response with a view angle of wheat, excluding atmospheric effects but simulating the response of a multispectral scanner, is analyzed. Spectra were taken continuously in the wavelength range of 0.45 to 2.4 microns at more than 1200 view/illumination directions with a 20 C spectral radiometer, and data were acquired six meters above four wheat canopies, each at a different stage of growth. The study shows that the canopy reflective response is a function of the illumination angle, the scanner view angle, and the wavelength; and the variation is greater at low solar variations.

Vanderbilt, V. C.↗
NASA NTRS1979

Atlas of soil reflectance properties

A compendium of soil spectral reflectance curves together with soil test results and site information is presented in an abbreviated manner listing those soil properties most important in influencing soil reflectance. Results are presented for 251 soils from 39 states and Brazil. A narrative key describes relationships between soil parameters and reflectance curves. All soils are classified according to the U.S. soil taxonomy and soil series name for ease of identification.

Stoner, E. R.↗
NASA NTRS1979

Multiband radiometer for field research

A multiband radiometer for field research with 8 bands between 0.4 and 12.5 micrometers is described. The data acquisition system will record the results from the radiometer, a precision radiation thermometer, and ancillary sources. The radiometer and data handling systems will be adaptable to helicopter, truck, to tripod platforms; the system will also be suitable for portable hand-held operation. The general characteristics of this system are that it will be (1) inexpensive to acquire, maintain, and operate, (2) simple to calibrate, (3) complete with data handling hardware and software, and (4) well-documented for use by researchers.

Robinson, B. F.↗
NASA NTRS1979

Calibration procedures for measurement of reflectance factor in remote sensing field research

A means by which measurements of the optical properties of crops and soils can be knowledgeably compared from site to site and instrument to instrument is presented in detail. The definition of bidirectional reflectance factor is reviewed and discussed. Procedures for field implementation are illustrated and discussed. Spectral and goniometric properties of laboratory and field reference surfaces and typical environmental subjects serve as a basis for analysis of uncertainties introduced by differing illumination conditions. Results of a comparison of the performance of three spectrometer systems are presented and discussed. It is concluded that intelligent use of the bidirectional reflectance factor technique is an accurate and practical means to obtain the spectral, optical properties of crops and soils needed for advancements in agricultural remote sensing.

Robinson, B. F.↗
NASA NTRS1977

Field measurements of the spectral response of natural waters

The spectral response (air-water interface reflectance and water-volume scattering) of turbid river water (99 mg/liter suspended solids) and relatively clear lake water (10 mg/liter suspended solids) was measured in situ with a field spectroradiometer. The influence of the river bottom on the spectral response of the water also was determined by using a modified Secchi disc approach. The results indicated that turbid river water had a higher spectral response than clear lake water (about 6 percent) in the red (0.6-0.7 micron) and near-infrared (0.7-0.9 micron) portions of the spectrum. Also, the reflectance characteristics of the river bottom did not influence the spectral response of the turbid river water when the water was deeper than 30 cm

Bartolucci, L. A.↗