As UAV imaging continues to expand, so too do the opportunities for improvements in data analysis. These
opportunities, in turn, present their own challenges including the need for real time radiometric and spectral calibration;
the continued development of quality metrics facilitating exploitation of strategic and tactical imagery; and the need to
correct for sensor and platform-induced artifacts in image data.
Getting Started with UAV Imaging Systems: A Radiometric Guide provides the tools technologists need to begin designing or analyzing the data product of a UAV imager. Covering the basics of target signatures, radiometric propagation, electro-optical systems, UAV platforms, and image quality, it is replete with examples that promote immediate application of the concepts. Reference materials at the end of each chapter, including many links to current systems and platforms, offer further guidance for readers. Engineers and scientists who specify instrument requirements; design, build, or test hardware; or analyze images for commercial, scientific, and military applications will find the book a useful addition to their working library.
“This text is a positive contribution to the ‘Getting Started’ literature in UAV imaging. The math and concepts are not simple but are presented and explained in a way that is accessible to a broad audience.”
—from a book review by Melissa J. Rura, Ph.D published in Photogrammatric Engineering & Remote Sensing 83(3), 176 (2017) [doi: 10.14358/PERS.83.3.175]
While efforts within the optics community focus on the development of high-quality systems and data products, comparatively little attention is paid to their use. Our standards for verification and validation are high; but in some user domains, standards are either lax or do not exist at all. In forensic imagery analysis, for example, standards exist to judge image quality, but do not exist to judge the quality of an analysis. In litigation, a high quality analysis is by default the one performed by the victorious attorney’s expert. This paper argues for the need to extend quality standards into the domain of imagery analysis, which is expected to increase in national visibility and significance with the increasing deployment of unmanned aerial vehicle—UAV, or “drone”—sensors in the continental U. S.. It argues that like a good radiometric calibration, made as independent of the calibrated instrument as possible, a good analysis should be subject to standards the most basic of which is the separation of issues of scientific fact from analysis results.
Expand your knowledge of Radiometry by taking the SPIE course Radiometry Revealed, with instructor Joseph Shaw. Click here to register.
Written from a systems engineering perspective, this Field Guide covers topics in optical radiation propagation, material properties, sources, detectors, system components, measurement, calibration, and photometry. Appendices provide material on SI units, conversion factors, source luminance data, and many other subjects. The book's organization and extensive collection of diagrams, tables, and graphs will enable the reader to efficiently identify and apply relevant information to radiometric problems arising amid the demands of today's fast-paced technical environment.
The material from this book was derived from a popular first-year graduate class taught by James M. Palmer for over twenty years at the University of Arizona College of Optical Sciences. This text covers topics in radiation propagation, radiometric sources, optical materials, detectors of optical radiation, radiometric measurements, and calibration. Radiometry forms the practical basis of many current applications in aerospace engineering, infrared systems engineering, remote sensing systems, displays, visible and ultraviolet sensors, infrared detectors of optical radiation, and many other areas. While several texts individually cover topics in specific areas, this text brings the underlying principles together in a manner suitable for both classroom teaching and a reference volume that the practicing engineer can use.
The level of discussion of the material is suitable for a class taught to advanced undergraduate students or graduate students. Although this book is not a theoretical treatment, the mathematics required to understand all equations include differential and integral calculus.
This text should be foremost in the toolkit of the practicing engineer or scientist working on radiometric problems in areas of optical engineering, electro-optical engineering, systems engineering, imagery analysis, and many others, allowing the technical professional to successfully apply radiometric principles in his or her work.
The controversy surrounding the origin of flashes on the Mt. Carmel FLIR videotape acquired on April 19, 1993, is introduced. The characteristics of muzzle flash are reviewed. A comparative weapons description is offered. The temporal, spatial, and radiance characteristics of thermal infrared muzzle flash are addressed. Data acquired from a field experiment are presented. The authors conclude that the spatial characteristics of muzzle flash enable its detection by equipment such as the FLIR in use at Mt. Carmel on April 19, 1993; that while flashes obtained in the field appear highly radiant, measurements are necessary to quantify their values; and that the temporal behavior of muzzle flash deserves further study.
The calibration method reported here makes use of the reflectances of several large, uniform areas determined from calibrated and atmospherically corrected SPOT Haute Resolution Visible (HRV) scenes of White Sands, New Mexico. These reflectances were used to predict the radiances in the first two channels of the NOAA-11 Advanced Very High Resolution Radiometer (AVHRR). The digital counts in the AVHRR image corresponding to these known reflectance areas were determined by the use of two image registration techniques. The plots of digital counts versus pixel radiance provided the calibration gains and offsets for the AVHRR. A reduction in the gains of 4 and 13 percent in channels 1 and 2 respectively was found during the period 1988-11-19 to 1990-6-21. An error budget is presented for the method and is extended to the case of cross-calibrating sensors on the same orbital platform in the Earth Observing System (EOS) era.
SC1123: The Building Blocks of IR Instrument Design
As infrared detector technology continues to migrate from government labs to commercial markets, photonic system designers see new technology opportunities to accomplish their design goals. Concurrently, developments in IR sources make near-infrared solutions attractive in terms of cost and performance. This course will help system designers, researchers, integrators, applications engineers, and related professionals navigate the infrared spectrum and trade off performance parameters for their solutions in applications such as laboratory imaging, UAV ("drone") imaging, spectrometry, and biomedical diagnostics, while also considering cost.
As Unmanned Aerial Vehicles (UAVs) continue to grow in importance in military and commercial applications, the need to understand radiometry with respect to many applications increases. This course presents the basic quantities and units of radiometry and photometry, and the propagation laws and approximations enabling flux transfer calculations. It introduces sources, blackbody radiation, optical material properties, detectors, and radiometric calibration. Applications are presented along with worked examples from the beginning of the course, and students have several opportunities to work problems on their own throughout the session.
SC1143: Component-Level Calibration: Sources, Detectors, and Measurement Hardware
While the calibration of advanced systems often features prominently in the optical spotlight, the calibration of components that go into these systems is no less important. In addition, some applications require only the use of a calibrated detector or source to meet measurement goals. This course will aid the component designer, systems designer, systems integrator, and other related professionals in understanding and filling the need for component-level calibration. It will survey source and detector calibration methods, address spectral calibration for instruments providing wavelength separation, survey test equipment calibration, and provide information enabling practitioners to perform a calibration uncertainty analysis at the component level.
SC1288: Problems in Autonomous Vehicle Imaging Systems
Put your knowledge of radiometry and photometry to work solving problems in autonomous systems, both UAVs and ground-based (self-driving cars.) This half-day short course delves into practical problems whose solutions are enabled by the passive sensors on emerging autonomous systems, emphasizing visible, near-infrared, and thermal infrared spectral regions. The course includes a limited amount of in-class problem solving practice under the instructor’s guidance.
This course takes basic radiometric principles and applies them to calculate the amount of radiation reaching a system's entrance aperture or focal plane for a variety of source-system combinations. It provides a brief review of radiometric propagation laws and offers a wide array of examples. It is application-oriented with problems in solar thermal systems, sun and sky irradiance delivered to a collector, sensor signals from specular and diffuse reflectors, infrared imagery, star sensing, and integrating spheres. Several examples from The Art of Radiometry are provided.
In this half-day course the basic quantities of radiometry, their units, and their relationships to electro-magnetic field quantities are presented. Photometry, its units, and conversion factors to older units are also addressed. The course covers the fundamentals of blackbody radiation generation and transfer. The basic equations needed to set up and solve problems are discussed.
The course introduces radiometric and photometric sources, detectors of optical radiation, instrumentation, and calibration. The supplementary textbook, <i>Introduction to Radiometry and Photometry</i> by Ross McCluney, is provided with the course and offers more detail in detector optical/ electrical characterization, color theory, and optical properties of specific materials.
This course is an ideal lead-in to SC944 The Radiometry Case Files, which provides many applied examples of the concepts introduced here.