Non-linear response of a class of hyper-spectral radiometers

The non-linear response of RAMSES hyperspectral radiometers was characterized in the 450 nm–800 nm spectral region. Results indicate inverse proportionality of the non-linearity with the output counts. The departure from linearity is generally within ±1.5% with maxima at the longest wavelengths. Notably, the consistency of results across different instruments suggests the possibility of applying corrections to the entire class of RAMSES radiometers with residuals generally lower than 0.3%. Finally, an analysis based on field measurements from different water types indicates that non-linearity can contribute up to 1.5% to the relative uncertainties affecting spectra of remote sensing reflectance.