April 2, 2024
Dan Scharpf, Ph.D.
Labsphere Chief Technologist
The JACIE (Joint Agency Commercial Imagery Evaluation) conference wrapped up last week after a series of excellent presentations and discussions about the current state of commercial earth imaging being utilized by NASA, NGA, NOAA, NRO, USDA, and USGS. Some key takeaways from my perspective related to imager calibration and the need to reduce uncertainty for better data and improved decision making:
- The launch date is what drives calibration: The launch will not wait, and if a system is not ready, the calibration is sometimes sacrificed.
- Pre-launch calibration is limited by cost and facilities.
- If Labsphere offered this as a service, would you utilize it?
- Guidelines from Calibration Best Practices documents are not being utilized.
- Calibration and Validation (Cal/Val) Needs to be thinking about calibrating hundreds of satellites, instead of one or two.
- Utilize AI/ML/DL
- More on-orbit cal is needed: Vicarious, on-board, cross-cal
- Utilize error detection and on-board computing
- Pre-Flight Calibration workshop at ESA, Nov 19-22, 2024 – Registration now open.
- Uncertainty Workshop
- Atmospheric uncertainty is a major contributor
- Geometric and Radiometric uncertainty must be included.
- For cross-calibration, a viewing difference of >10° can lead to 20% uncertainty (k=2) due to BRDF.
- Always include the coverage factor, k=1, or k=2 when reporting uncertainty.
- Calibration is critical: Pre-launch, on-board, vicarious, and cross-calibration. More calibration increases the confidence in the data.
Labsphere Presentations:
Compact Jones Source for Next Generation Earth Observation Satellites in VNIRSWIR and MWIR
Developing a Vacuum-Compatible, Spectrally-Tunable, Low-Volume Integrated Source (LVIS)
On Demand Vicarious Calibration for Analysis Ready Data (ARD) – The FLARE Network
All Presentations: https://calval.cr.usgs.gov/apps/JACIEsearch