The Insight library explains the physics behind the display. Begin with three questions: what did the sensor measure, which processing steps created this product, and how much of its interpretation is constrained by independent evidence?
Reading a radar image
Brightness in a SAR intensity image is related to calibrated backscatter, not visible colour. Incidence angle, surface roughness, dielectric properties, vegetation, polarisation and wavelength all shape the signal. Layover and shadow can displace or hide terrain features. A black region may indicate smooth water, radar shadow or another low-return condition; context is essential.
Reading phase and change
Complex SAR products preserve phase as well as amplitude. A phase difference between suitable, coherent acquisitions can encode relative path change, but also contains topographic, atmospheric and noise contributions. Coherence, baseline geometry and reference choice help determine whether an interferogram supports a displacement estimate.
Reading a reconstruction
A modelled map is an inference from measurements and assumptions. Ask whether the inputs were calibrated, which spatial support is represented, what priors or regularisation were used, where the model fails and whether an independent reference was used. The most important visual clue may be a gap or uncertainty layer.