The Remote Sensing Group (RSG) at the University of Arizona Optical Sciences Center has been performing high accuracy laboratory calibration for over 20 years. This work has been done both in support of our work in vicarious calibration of space-borne and airborne imaging sensors and as a standalone means of achieving NIST-traceable radiometric calibration. The solar radiation-based calibration (SRBC) has in the past been a way for the RSG to verify calibration results and to achieve continued calibration of field-grade instruments. This paper presents multiple SRBC results for multiple laboratory-grade radiometers. These results are compared with laboratory calibrations and studied for their merit as a sole means of high-accuracy calibration.