Camera calibration program in the United States past

Camera calibration program in the United States: past, present, and future U. S. Department of the Interior U. S. Geological Survey Radiometric and Geometric Calibration Workshop

Background: • USGS camera calibration responsibility • Responsibility transferred to the USGS in 1973 • Laboratory calibration using multi-collimators • Calibration instrument designed for metric 230 - x 230 -mm film-base aerial cameras Radiometric and Geometric Calibration Workshop

Background: • Evolution of digital technology: • Photogrammetric scanners over fifteen years ago • Small-format cameras being used for years by a small sector of the mapping community • Large-format aerial cameras have been in development for years and have emerged • Non-optical sensors playing a bigger role • 1 -meter and sub-meter products from satellites Radiometric and Geometric Calibration Workshop

Background: • USGS failure to be prepared for digital cameras resulted in: • • Lack of experience with digital cameras Lack of instrumentation to continue calibrations Lack of upgrade strategy from analog to digital Lack of standards and policies Radiometric and Geometric Calibration Workshop

Complicating issues: • Inability to perform laboratory calibration on small format digital cameras • Different designs of digital cameras • Different hardware/software solutions • Integration of cameras with other systems such as IMU and airborne-GPS equipment Radiometric and Geometric Calibration Workshop

The bottom line for calibration: • Ensuring quality of the end-product But: • Who does it? • How is it done? Radiometric and Geometric Calibration Workshop

Current approval authorities: • For now: • USGS (cameras) • USGS and other agency contracting offices (product characterizations) • Future may include: • Government-approved independent evaluators/consultants • UL-type organization Radiometric and Geometric Calibration Workshop

How? • • • Component calibration (camera calibration) System calibration (LIDAR systems) Process evaluation (error budget analysis) Product characterization (satellite products) ISO certification (quality management plan) Radiometric and Geometric Calibration Workshop

USGS camera calibration efforts: • Stabilization of analog calibration instrument • Development and installation of interim calibration capability for small-format cameras • Development of in-situ calibration site and software Radiometric and Geometric Calibration Workshop

Analog calibration: Radiometric and Geometric Calibration Workshop

Analog calibration: • Maintain current policy • Continue to provide camera calibrations on a cost recovery basis Radiometric and Geometric Calibration Workshop

Interim digital capability at EDC: Radiometric and Geometric Calibration Workshop

Interim digital capability: • Testing stability of calibrations with USGS camera • Calibration of other cameras on a research basis • Comparison of results with other laboratory calibration methods • Comparison of results with in-situ calibration approach Radiometric and Geometric Calibration Workshop

In-situ calibration: • Initial operating capability to include site preparation, software development, and testing with USGS camera • Operational testing with other cameras for comparisons in stability • Extension of software to allow other in-situ sites Radiometric and Geometric Calibration Workshop

Product Characterizations over NASA Stennis Test Range SSC Remote Sensing Radial Target and Edge Response Targets Radiometric and Geometric Calibration Workshop

Product Characterizations: • • Performed under USGS/NASA agreement First round funded by USGS Data acquisition over Stennis test site Data provider generates end-product to be evaluated (e. g. , 1 -foot resolution DOQ) • NASA performs evaluation • USGS provides acceptance letter Radiometric and Geometric Calibration Workshop

Future work: • • • Perform radiometry testing Comparison of calibration methods Evaluation of product characterizations Development of in-situ calibration standards Development of related standards Radiometric and Geometric Calibration Workshop

Contact information: • George Lee, USGS, 650 -329 -4255, gylee@usgs. gov • Greg Stensaas, USGS, 605 -594 -2569, stensaas@usgs. gov • Vicki Zanoni, NASA, 228 -688 -2305, vzanoni@ssc. nasa. gov Radiometric and Geometric Calibration Workshop