Category: Processing and quality
Radiometry
Radiometry is the measurement and calibration of electromagnetic energy recorded by a sensor.
Also known as: radiometric calibration, radiometric consistency
Expanded definition
Radiometry covers how a sensor records energy and how those measurements are calibrated and scaled into physical quantities like radiance or reflectance.
Radiometric consistency matters for time series, mosaics, and machine learning. If radiometry shifts between processing versions or sensors, you can get false change, unstable indices, and models that do not generalize.
Related terms
Radiance
Radiance is the raw physical quantity measured by optical sensors, representing energy reaching the sensor.
Reflectance
Reflectance is the fraction of incoming light that a surface reflects, commonly used for analysis and comparison.
Harmonization
Harmonization reduces differences between scenes or sensors so values are more comparable across time.
BRDF
BRDF describes how reflectance changes with viewing and illumination geometry, affecting apparent brightness across scenes.