Radiometric Calibration and Characterization of Large-format Digital Photogrammetric Sensors in a Test Field

Abstract

Test field calibration is an attractive approach to calibrating and characterizing the radiometry of airborne imaging instruments. In this study, a method for radiometric test field calibration for digital photogrammetric instruments is developed, and it is used to evaluate the radiometric performance of large-format photogrammetric sensors the ADS40, the DMC, and the UltraCam D. In the study, linearity, dynamic range, sensitivity, and absOlute calibration were evaluated. The results demonstrated the high radiometric quality of the sensors tested. All the sensors were linear in response. The DMC used the 12-bit dynamic range entirely, while the ADS40 and the UltraCam D indicated close to the 13-bit dynamic range. The sensors performed quite differently with respect to sensitivity. With the DMC and the UltraCam D a risk of overexposure appeared, while the color channels of the ADS40 showed low sensitivity. Because the sensors were linear in response, they could be absolutely calibrated using linear models.

Acquisition of Bidirectional Reflectance Factor Dataset Using a Micro Unmanned Aerial Vehicle and a Consumer Camera

“…This in turn caused overestimation of the specular characteristics of the actual target BRF. For future measurements better reference targets, such as those used for large-format digital photogrammetric sensors [19], are needed. However, even with these limitations, the quality of the data is reasonably good.…”

Digital Airborne Photogrammetry—A New Tool for Quantitative Remote Sensing?—A State-of-the-Art Review On Radiometric Aspects of Digital Photogrammetric Images

“…On-board calibration determines the sensor calibration in fight conditions using various on-board calibrators or natural light sources (the Sun, the Moon) [34,40]. Vicarious methods determine the system calibration in flight conditions utilizing targets present in the scene, typically either artificial targets or natural targets, such as playa, desert sand and salt flats or clouds; to determine accurately the radiance entering the system, vicarious methods require either accurate information on atmospheric conditions and object reflectance (reflectance-based method), or simultaneous determination of the at-sensor radiance by a calibrated radiometer (radiance-based method) [1,2,34,41,42]. Self-calibration is a concept commonly used with geometry [43,44] but can be generalized to concern radiometry as well; it means the determination or improvement of system calibration using the actual mapping data.…”

“…In Finland, comprehensive campaigns with various systems have been carried out at the Sjökulla test field [1,2,13,50]. Institut Cartogràphic Catalonia (ICC) has performed comprehensive campaigns with DMC at the Banyoles test field [38,51,52].…”

“…An important novel feature of the digital systems, in comparison to analog systems, is their high radiometric potential, which was empirically proven by Honkavaara [1] and Markelin et al [2]. In these baseline investigations, radiometric properties of all commercial first generation photogrammetric large-format sensor types were studied using imagery collected in 2004 and 2005.…”

Users’ Assessment of Orthoimage Photometric Quality for Visual Interpretation of Agricultural Fields

“…While there is a broad literature on radiometric and photometric aspects of images, its main focus is on radiometry during image production [14,17,18]. Typically, quality assessment metrics are designed for natural, close-range images (e.g., tested using the Tampere Image Database 2008 (TID2008)) and intended for evaluation of full-reference image [19] or video [20].…”