Solar radiation based calibration results from an ultra-portable field transfer radiometer used in vicarious calibrations

Design of an ultra-portable field-capable short wave infrared transfer radiometer supporting Earth observing sensor calibration

“…Lollipop testing is a beneficial tool used often in RSG, NIST, GSFC and other labs for instrument testing and other test setups to evaluate or quantify effects and signal levels from outside of an instrument FOV. 1,[16][17][18] The solution to this problem was to add a "snout" with an aperture in front of the filter wheel entrance. The aperture diameters are designed slightly larger than the defined FOV at this distance and serve as baffles for the system.…”

“…In the years since the two VNIR CaTSSITTR ultra-portable instruments were completed and ready for calibration work, they have travelled extensively and been used for many different calibration purposes. [1][2][3][4][5] Initially, it was unclear what need in the calibration community would exist for these instruments outside of the NASA Goddard Space Flight Center (GSFC) and RSG partnership. They were designed specifically as calibration companions for the Ground Viewing Radiometers (GVR) deployed at NASA and United States Geological Survey (USGS) field locations, most notably the Radiometric Calibration Test Site (RadCaTS) at Railroad Valley Dry Lake (RRV), Nevada.…”

“…Calibration groups, especially those collaborating in the Radiometric Calibration Network (RadCalNet) 10 , among other needs, strongly desired a straightforward, repeatable method of comparing spectral radiance between laboratories and field calibration sites around the world. [1][2][3][4][5] While the VNIR CaTSSITTR design was risky in terms of a dramatic size, weight and power reduction, there have been many successful Silicon-based instruments made for high accuracy and portability. If anything, the larger risk for CaTSSITTR design is related to support electronics and their ability to maintain high accuracy at small size.…”

Evaluating commercial tablet screens for use as portable spectral radiance calibration assessment sources, specifically in support of field-deployed ground viewing radiometers

“…These CaTSSITTR instruments have since been used for transfer radiometry in support of various field and laboratory calibrations around the world, much in support of the Radiometric Calibration Network, or RadCalNet, an initiative of the Working Group on Calibration and Validation of the Committee on Earth Observation Satellites (CEOS). [4][5][6][7][8][9] CaTSSITTRs are designed to provide reliable, calibrated spectral radiance results. Their short and long term stability, along with proven linearity, low noise operation, and other attributes, make them great radiometers for testing sources.…”

Radiance-based and reflectance-based retrievals of surface reflectance for vicarious calibration

“…Based on recommendations from lessons learned during joint field campaigns in 2009 and 2010 [4], the Remote Sensing Group (RSG) of the College of Optical Sciences at the University of Arizona developed a portable transfer radiometer, named Calibration and Test Site, SI-Traceable Transfer Radiometer (CaTSSITTR), to act as a transfer standard to link test-site traceability [5]. A description of CaTSSITTR and its laboratory calibration can be found in the reference [6] but an overview is provided here to provide context for the current work.…”