Which of the following is not a type of radiometric correction used in image processing when there is interference with the radiance measured by an instrument?

• A. Noise removal
• B. Sun angle correction
• C. Haze correction
• D. Ozone depletion correction

Answer: (D)

Radiometric correction aims to adjust the measured radiance so the data reflect the true surface signal by removing sensor noise, accounting for illumination geometry, and mitigating atmospheric interference. Noise removal directly tackles the random and fixed-pattern noise introduced by the instrument, cleaning up the signal. Sun angle correction addresses how the sun’s position changes illumination, normalizing brightness so images taken at different times can be compared fairly. Haze correction deals with atmospheric scattering that adds a veil and reduces scene contrast, helping recover clearer radiance from the surface.

Ozone depletion correction is not treated as a separate radiometric correction step. Effects of ozone on transmission are handled within atmospheric correction using radiative transfer models, rather than as an independent correction category.